Exhibit 10.1

On or before the Maturity Date set forth above, FOR VALUE RECEIVED, the undersigned promise(s) to pay to the order of COMERICA BANK (herein called “Bank”), at any office of the Bank in the State of Michigan, the principal sum of FIFTY MILLION AND 00/100 DOLLARS ($50,000,000.00), or so much of said sum as has been advanced and is then outstanding under this Note, together with interest thereon at the Daily Adjusting LIBOR Rate plus the Applicable Margin, except during any period of time during which, in accordance with the terms and conditions of this Note, the Indebtedness hereunder shall bear interest at the Prime Referenced Rate plus the Applicable Margin.

This Note is made in connection with a letter/loan agreement between the undersigned and Bank dated of even date herewith (as it may be amended from time to time, the “Agreement”), the provisions of which are incorporated herein by this reference.

Anything in this Note to the contrary notwithstanding, the aggregate principal amount at any one time outstanding under this Note shall never exceed the lesser of the Maximum Line Amount (as defined in the Agreement) or the Borrowing Base (as defined in the Agreement). The undersigned shall immediately make all payments necessary to comply with this provision. The undersigned hereby acknowledges and agrees that nothing in this paragraph imposes any obligation on the Bank to make or continue any advances under this Note.

This Note is a note under which advances, repayments and re-advances may be made from time to time, subject to the terms and conditions of this Note; provided, however, in no event shall Bank be obligated to make any advances or re-advances hereunder (notwithstanding anything expressed or implied herein or elsewhere to the contrary) if a Default has occurred or exists or would result from the making of such advance or re-advance or if any of the conditions to the making of advances or re-advances in this Note, the Agreement or the other Loan Documents (as defined in the Agreement) have not been satisfied in Bank’s sole determination.

Accrued and unpaid interest on the unpaid principal balance outstanding hereunder shall be payable monthly, in arrears, on the first Business Day of each month, until maturity (whether as stated herein, by acceleration, or otherwise). Interest accruing hereunder shall be computed on the basis of a year of 360 days, and shall be assessed for the actual number of days elapsed, and in such computation, effect shall be given to any change in the applicable interest rate as a result of any change in the Daily Adjusting LIBOR Rate or, to the extent applicable, the Prime Referenced Rate on the date of each such change.

From and after the occurrence of any Default hereunder, and so long as any such Default remains unremedied or uncured thereafter, the Indebtedness outstanding under this Note shall bear interest at a per annum rate of three percent (3%) above the otherwise applicable interest rate hereunder, which interest shall be payable upon demand. In addition to the foregoing, a late payment charge equal to five percent (5%) of each late payment hereunder may be charged on any payment not received by Bank within ten (10) calendar days after the payment due date therefor, but acceptance of payment of any such charge shall not constitute a waiver of any Default hereunder.

In no event shall the interest payable under this Note at any time exceed the maximum rate permitted by law.

The amount and date of each advance hereunder, its applicable interest rate and the amount and date of any repayment shall be noted on Bank’s records, which records shall be conclusive evidence thereof, absent manifest error; provided, however, any failure by Bank to make any such notation, or any error in any such notation, shall not relieve the undersigned of its/their obligations to repay Bank all amounts payable by the undersigned to Bank under or pursuant to this Note, when due in accordance with the terms hereof.

In the event that the Daily Adjusting LIBOR Rate is not available to the undersigned as the basis for the applicable interest rate hereunder for the principal Indebtedness outstanding hereunder in accordance with the terms of this Note, the Prime Referenced Rate plus the Applicable Margin shall be the applicable interest rate hereunder in respect of such Indebtedness for such period, subject in all respects to the terms and conditions of this Note.

In the event that any payment under this Note becomes due and payable on any day which is not a Business Day, the due date thereof shall be extended to the next succeeding Business Day, and, to the extent applicable, interest shall continue to accrue and be payable thereon during such extension at the rates set forth in this Note.

All payments to be made by the undersigned to Bank under or pursuant to this Note shall be in immediately available United States funds, without setoff or counterclaim, and in the event that any payments submitted hereunder are in funds not available until collected, said payments shall continue to bear interest until collected.

The undersigned may prepay all or part of the outstanding balance of any Indebtedness hereunder at any time without premium or penalty. Any prepayment hereunder shall also be accompanied by the payment of all accrued and unpaid interest on the amount so prepaid.

If, at any time, Bank determines that, (a) Bank is unable to determine or ascertain the Daily Adjusting LIBOR Rate, or (b) by reason of circumstances affecting the foreign exchange and interbank markets generally, deposits in eurodollars in the applicable amounts or for the relative maturities are not being offered to Bank, or (c) the Daily Adjusting LIBOR Rate plus the Applicable Margin will not accurately or fairly cover or reflect the cost to Bank of maintaining any of the Indebtedness under this Note based upon the Daily Adjusting LIBOR Rate, then Bank shall forthwith give notice thereof to the undersigned.  Thereafter, until Bank notifies the undersigned that such conditions or circumstances no longer exist, the Prime Referenced Rate plus the Applicable Margin shall be the applicable interest rate for all Indebtedness hereunder during such period of time.

If any Change in Law shall make it unlawful or impossible for the Bank (or its LIBOR Lending Office) to make or maintain any of the Indebtedness under this Note with interest based upon the Daily Adjusting LIBOR Rate, Bank shall forthwith give notice thereof to the undersigned.  Thereafter, until Bank notifies the undersigned that such conditions or circumstances no longer exist, the Prime Referenced Rate plus the Applicable Margin shall be the applicable interest rate for all Indebtedness hereunder during such period of time.

If any Change in Law shall: (a) subject Bank (or its LIBOR Lending Office) to any tax, duty or other charge with respect to this Note or any Indebtedness hereunder, or shall change the basis of taxation of payments to Bank (or its LIBOR Lending Office) of the principal of or interest under this Note or any other amounts due under this Note in respect thereof (except for changes in the rate of tax on the overall net income of Bank or its LIBOR Lending Office imposed by the jurisdiction in which Bank’s principal executive office or LIBOR Lending Office is located); or (b) impose, modify or deem applicable any reserve (including, without limitation, any imposed by the Board of Governors of the Federal Reserve System), special deposit or similar requirement against assets of, deposits with or for the account of, or credit extended by Bank (or its LIBOR Lending Office), or shall impose on Bank (or its LIBOR Lending Office) or the foreign exchange and interbank markets any other condition affecting this Note or the Indebtedness hereunder; and the result of any of the foregoing is to increase the cost to Bank of maintaining any part of the Indebtedness hereunder or to reduce the amount of any sum received or receivable by Bank under this Note by an amount deemed by the Bank to be material, then the undersigned shall pay to Bank, within fifteen (15) days of the undersigned’s receipt of written notice from Bank demanding such compensation, such additional amount or amounts as will compensate Bank for such increased cost or reduction.  A certificate of Bank, prepared in good faith and in reasonable detail by Bank and submitted by Bank to the undersigned, setting forth the basis for determining such additional amount or amounts necessary to compensate Bank shall be conclusive and binding for all purposes, absent manifest error.

In the event that any Change in Law affects or would affect the amount of capital required or expected to be maintained by Bank (or any corporation controlling Bank), and Bank determines that the amount of such capital is increased by or based upon the existence of any obligations of Bank hereunder or the maintaining of any Indebtedness hereunder, and such increase has the effect of reducing the rate of return on Bank’s (or such controlling corporation’s) capital as a consequence of such obligations or the maintaining of such Indebtedness hereunder to a level below that which Bank (or such controlling corporation) could have achieved but for such circumstances (taking into consideration its policies with respect to capital adequacy), then the undersigned shall pay to Bank, within fifteen (15) days of the undersigned’s receipt of written notice from Bank demanding such compensation, additional amounts as are sufficient to compensate Bank (or such controlling corporation) for any increase in the amount of capital and reduced rate of return which Bank reasonably determines to be allocable to the existence of any obligations of the Bank hereunder or to maintaining any Indebtedness hereunder.  A certificate of Bank as to the amount of such compensation, prepared in good faith and in reasonable detail by the Bank and submitted by Bank to the undersigned, shall be conclusive and binding for all purposes absent manifest error.

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This Note and any other indebtedness and liabilities of any kind of the undersigned (or any of them) to the Bank, and any and all modifications, renewals or extensions of it, whether joint or several, contingent or absolute, now existing or later arising, and however evidenced and whether incurred voluntarily or involuntarily, known or unknown, or originally payable to the Bank or to a third party and subsequently acquired by Bank including, without limitation, any late charges; loan fees or charges; overdraft indebtedness; costs incurred by Bank in establishing, determining, continuing or defending the validity or priority of any security interest, pledge or other lien or in pursuing any of its rights or remedies under any loan document (or otherwise) or in connection with any proceeding involving the Bank as a result of any financial accommodation to the undersigned (or any of them); and reasonable costs and expenses of attorneys and paralegals, whether inside or outside counsel is used, and whether any suit or other action is instituted, and to court costs if suit or action is instituted, and whether any such fees, costs or expenses are incurred at the trial court level or on appeal, in bankruptcy, in administrative proceedings, in probate proceedings or otherwise (collectively “Indebtedness”) are secured by and the Bank is granted a security interest in and lien upon all items deposited in any account of any of the undersigned with the Bank and by all proceeds of these items (cash or otherwise), all account balances of any of the undersigned from time to time with the Bank, by all property of any of the undersigned from time to time in the possession of the Bank and by any other collateral, rights and properties described in the Agreement, the Loan Documents (as defined in the Agreement), and each and every deed of trust, mortgage, security agreement, pledge, assignment and other security or collateral agreement which has been, or will at any time(s) later be, executed by any (or all) of the undersigned to or for the benefit of the Bank (collectively “Collateral”). Notwithstanding the above, (i) to the extent that any portion of the Indebtedness is a consumer loan, that portion shall not be secured by any deed of trust or mortgage on or other security interest in any of the undersigned’s principal dwelling or in any of the undersigned’s real property which is not a purchase money security interest as to that portion, unless expressly provided to the contrary in another place, or (ii) if the undersigned (or any of them) has (have) given or give(s) Bank a deed of trust or mortgage covering California real property, that deed of trust or mortgage shall not secure this Note or any other indebtedness of the undersigned (or any of them), unless expressly provided to the contrary in another place, or (iii) if the undersigned (or any of them) has (have) given or give(s) the Bank a deed of trust or mortgage covering real property which, under Texas law, constitutes the homestead of such person, that deed of trust or mortgage shall not secure this Note or any other indebtedness of the undersigned (or any of them) unless expressly provided to the contrary in another place.

If (a) the undersigned (or any of them) or any guarantor under a guaranty of all or part of the Indebtedness (“guarantor”) (i) fail(s) to pay this Note or any of the Indebtedness when due, by maturity, acceleration or otherwise, or fail(s) to pay any Indebtedness owing on a demand basis upon demand; or (ii) fail(s) to comply with any of the terms or provisions of any agreement between the undersigned (or any of them) or any guarantor and the Bank, and any such failure continues beyond any applicable grace or cure period, if any, expressly provided with respect thereto; or (iii) become(s) insolvent or the subject of a voluntary or involuntary proceeding in bankruptcy, or a reorganization, arrangement or creditor composition proceeding, (if a business entity) cease(s) doing business as a going concern, (if a natural person) die(s) or become(s) incompetent, (if a partnership) dissolve(s) or any general partner of it dies, becomes incompetent or becomes the subject of a bankruptcy proceeding, or (if a corporation or a limited liability company) is the subject of a dissolution, merger or consolidation; or (b) any warranty or representation made by any of the undersigned or any guarantor in connection with this Note or any of the Indebtedness shall be discovered to be untrue or incomplete; or (c) there is any termination, notice of termination, or breach of any guaranty, pledge, collateral assignment or subordination agreement relating to all or any part of the Indebtedness; or (d) there is any failure by any of the undersigned or any guarantor to pay when due any of its indebtedness (other than to the Bank) or in the observance or performance of any term, covenant or condition in any document evidencing, securing or relating to such indebtedness; or (e) the Bank deems itself insecure, believing that the prospect of payment or performance of this Note or any of the Indebtedness is impaired or shall fear deterioration, removal or waste of any of the Collateral; or (f) there is filed or issued a levy or writ of attachment or garnishment or other like judicial process upon the undersigned (or any of them) or any guarantor or any of the Collateral, including, without limit, any accounts of the undersigned (or any of them) or any guarantor with the Bank; or (g) an “Event of Default” as defined in the Agreement occurs or exists; then the Bank, upon the occurrence and at any time during the continuance or existence of any of these events (each a “Default”), may, at its option and without prior notice to the undersigned (or any of them), declare any or all of the Indebtedness to be immediately due and payable (notwithstanding any provisions contained in the evidence of it to the contrary), sell or liquidate all or any portion of the Collateral, set off against the Indebtedness any amounts owing by the Bank to the undersigned (or any of them), charge interest at the default rate provided in the document evidencing the relevant Indebtedness and exercise any one or more of the rights and remedies granted to the Bank by any agreement with the undersigned (or any of them) or given to it under applicable law.

The undersigned authorize(s) the Bank to charge any account(s) of the undersigned (or any of them) with the Bank for any and all sums due hereunder when due; provided, however, that such authorization shall not affect any of the undersigned’s obligation to pay to the Bank all amounts when due, whether or not any such account balances that are maintained by the undersigned with the Bank are insufficient to pay to the Bank  any amounts when due, and to the extent

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that are insufficient to pay to the Bank all such amounts, the undersigned shall remain liable for any deficiencies until paid in full.

If this Note is signed by two or more parties (whether by all as makers or by one or more as an accommodation party or otherwise), the obligations and undertakings under this Note shall be that of all and any two or more jointly and also of each severally. This Note shall bind the undersigned, and the undersigned’s respective heirs, personal representatives, successors and assigns.

The undersigned waive(s) presentment, demand, protest, notice of dishonor, notice of demand or intent to demand, notice of acceleration or intent to accelerate, and all other notices, and agree(s) that no extension or indulgence to the undersigned (or any of them) or release, substitution or nonenforcement of any security, or release or substitution of any of the undersigned, any guarantor or any other party, whether with or without notice, shall affect the obligations of any of the undersigned. The undersigned waive(s) all defenses or right to discharge available under Section 3-605 of the Michigan Uniform Commercial Code and waive(s) all other suretyship defenses or right to discharge. The undersigned agree(s) that the Bank has the right to sell, assign, or grant participations or any interest in, any or all of the Indebtedness, and that, in connection with this right, but without limiting its ability to make other disclosures to the full extent allowable, the Bank may disclose all documents and information which the Bank now or later has relating to the undersigned or the Indebtedness.  The undersigned agree(s) that the Bank may provide information relating to this Note or relating to the undersigned to the Bank’s parent, affiliates, subsidiaries and service providers.

The undersigned agree(s) to pay to or reimburse Bank, or any other holder or owner of this Note, on demand, any and all costs and expenses of Bank or such holder or owner (including, without limit, court costs, legal expenses and reasonable attorneys’ fees, whether inside or outside counsel is used, whether or not suit is instituted, and, if suit is instituted, whether at the trial court level, appellate level, in a bankruptcy, probate or administrative proceeding or otherwise) incurred in connection with the preparation, execution, delivery, amendment, administration, and performance of this Note and the related documents, or incurred in collecting or attempting to collect this Note or the Indebtedness, or incurred in any other matter or proceeding relating to this Note or the Indebtedness.

The undersigned acknowledge(s) and agree(s) that there are no contrary agreements, oral or written, establishing a term of this Note and agree(s) that the terms and conditions of this Note may not be amended, waived or modified except in a writing signed by an officer of the Bank expressly stating that the writing constitutes an amendment, waiver or modification of the terms of this Note. As used in this Note, the word  “undersigned” means, individually and collectively, each maker, accommodation party, endorser and other party signing this Note in a similar capacity. If any provision of this Note is unenforceable in whole or part for any reason, the remaining provisions shall continue to be effective. THIS NOTE SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE INTERNAL LAWS OF THE STATE OF MICHIGAN, WITHOUT REGARD TO CONFLICT OF LAWS PRINCIPLES.

For the purposes of this Note, the following terms have the following meanings:

“Applicable Margin” means two and seventy-five hundredths percent (2.75%) per annum.

“Business Day” means any day, other than a Saturday, Sunday or any other day designated as a holiday under Federal or applicable State statute or regulation, on which Bank is open for all or substantially all of its domestic and international business (including dealings in foreign exchange) in Detroit, Michigan, and, in respect of notices and determinations relating to the Daily Adjusting LIBOR Rate, also a day on which dealings in dollar deposits are also carried on in the London interbank market and on which banks are open for business in London, England.

“Change in Law” means the occurrence, after the date hereof, of any of the following: (i) the adoption or introduction of, or any change in any applicable law, treaty, rule or regulation (whether domestic or foreign) now or hereafter in effect and whether or not applicable to Bank on such date, or (ii) any change in interpretation, administration or implementation thereof of any such law, treaty, rule or regulation by any Governmental Authority, or (iii) the issuance, making or implementation by any Governmental Authority of any interpretation, administration, request, regulation, guideline, or directive (whether or not having the force of law), including any risk-based capital guidelines.  For purposes of this definition, (x) a change in law, treaty, rule, regulation, interpretation, administration or implementation shall include, without limitation, any change made or which becomes effective on the basis of a law, treaty, rule, regulation, interpretation administration or implementation then in force, the effective date of which change is delayed by the terms of such law, treaty, rule, regulation, interpretation, administration or implementation, and (y) the Dodd-Frank Wall Street Reform and Consumer Protection Act (Pub. L. 111-203, H.R. 4173) and all requests, rules, regulations, guidelines, interpretations or directives promulgated thereunder or issued in connection therewith shall be deemed to be a “Change in

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Law”, regardless of the date enacted, adopted, issued or promulgated, whether before or after the date hereof, and (z) all requests, rules, guidelines or directives promulgated by the Bank for International Settlements, the Basel Committee on Banking Supervision (or any successor or similar authority) or the United States regulatory authorities, in each case pursuant to Basel III, shall each be deemed to be a “Change in Law”, regardless of the date enacted, adopted, issued or implemented.

“Daily Adjusting LIBOR Rate” means, for any day, a per annum interest rate which is equal to the quotient of the following:

(a)                               for any day, the per annum rate of interest determined on the basis of the rate for deposits in United States Dollars for a period equal to one (1) month appearing on Page BBAM of the Bloomberg Financial Markets Information Service as of 11:00 a.m. (Detroit, Michigan time) (or as soon thereafter as practical) on such day, or if such day is not a Business Day, on the immediately preceding Business Day.  In the event that such rate does not appear on Page BBAM of the Bloomberg Financial Markets Information Service (or otherwise on such Service) on any day, the “Daily Adjusting LIBOR Rate” for such day shall be determined by reference to such other publicly available service for displaying eurodollar rates as may be reasonably selected by Bank, or, in the absence of such other service, the “Daily Adjusting LIBOR Rate” for such day shall, instead, be determined based upon the average of the rates at which Bank is offered dollar deposits at or about 11:00 a.m. (Detroit, Michigan time) (or as soon thereafter as practical), on such day, or if such day is not a Business Day, on the immediately preceding Business Day, in the interbank eurodollar market in an amount comparable to the principal amount outstanding hereunder and for a period of one (1) month;

divided by

(b)                              1.00 minus the maximum rate (expressed as a decimal) on such day at which Bank is required to maintain reserves on “Euro-currency Liabilities” as defined in and pursuant to Regulation D of the Board of Governors of the Federal Reserve System or, if such regulation or definition is modified, and as long as Bank is required to maintain reserves against a category of liabilities which includes eurodollar deposits or includes a category of assets which includes eurodollar loans, the rate at which such reserves are required to be maintained on such category;

provided, however, in no event and at no time shall the Daily Adjusting LIBOR Rate be less than twenty five hundredths of one percent (.25%) per annum.

“Governmental Authority” means the government of the United States of America or any other nation, or of any political subdivision thereof, whether state or local, and any agency, authority, instrumentality, regulatory body, court, central bank or other entity exercising executive, legislative, judicial, taxing, regulatory or administrative powers or functions of or pertaining to government (including, without limitation, any supranational bodies such as the European Union or the European Central Bank).

“LIBOR Lending Office” means Bank’s office located in the Cayman Islands, British West Indies, or such other branch of Bank, domestic or foreign, as it may hereafter designate as its LIBOR Lending Office by notice to the undersigned.

“Prime Rate” means the per annum interest rate established by Bank as its prime rate for its borrowers, as such rate may vary from time to time, which rate is not necessarily the lowest rate on loans made by Bank at any such time.

“Prime Referenced Rate” means a per annum interest rate which is equal to the Prime Rate, but in no event less than two and one-half percent (2.50%) per annum.

No delay or failure of Bank in exercising any right, power or privilege hereunder shall affect such right, power or privilege, nor shall any single or partial exercise thereof preclude any further exercise thereof, or the exercise of any other power, right or privilege.  The rights of Bank under this Note are cumulative and not exclusive of any right or remedies which Bank would otherwise have, whether by other instruments or by law.

THE MAXIMUM INTEREST RATE SHALL NOT EXCEED 25% PER ANNUM OR THE HIGHEST APPLICABLE USURY CEILING, WHICHEVER IS LESS.

THE UNDERSIGNED AND BANK, BY ACCEPTANCE OF THIS NOTE, ACKNOWLEDGE THAT THE RIGHT TO TRIAL BY JURY IS A CONSTITUTIONAL ONE, BUT THAT IT MAY BE WAIVED UNDER CERTAIN CIRCUMSTANCES.  TO THE EXTENT PERMITTED BY LAW, EACH PARTY, AFTER CONSULTING (OR HAVING HAD THE OPPORTUNITY

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TO CONSULT) WITH COUNSEL OF THEIR CHOICE, KNOWINGLY AND VOLUNTARILY, AND FOR THEIR MUTUAL BENEFIT, WAIVES ANY RIGHT TO TRIAL BY JURY IN THE EVENT OF LITIGATION REGARDING THE PERFORMANCE OR ENFORCEMENT OF, OR IN ANY WAY RELATED TO, THIS NOTE OR THE INDEBTEDNESS.

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