Exhibit 10.1

GUGGENHEIM CORPORATE FUNDING, LLC

300 Madison Avenue, 10^th Floor

New York, NY 10017

April 23, 2015

API Technologies Corp.

4705 S. Apopka Vineland Road, Suite 210

Orlando, Florida 32819

Attention: Brian R. Kahn, Chairman

Project Indigo

Commitment Letter

Ladies and Gentlemen:

Subject to the terms and conditions described in this letter and the attached Term Sheet (“Exhibit A”, and together with this letter, the “Commitment Letter”), (a) Guggenheim Corporate Funding, LLC (acting alone or through or with affiliates selected by it) (“GCF”) agrees to provide the services referred to in the next succeeding paragraph and (b) each of the other entities which has signed below as a commitment party (each a “Commitment Party”, and collectively, the “Commitment Parties”) is pleased to offer its commitment to provide, severally (and not jointly), to API Technologies Corp., a Delaware corporation (the “Borrower”) the portion of the Amendment No. 3 Incremental Term Loan (as defined in Exhibit A) set forth opposite its name on Schedule I hereto with respect to the Borrower under the Borrower’s Credit Agreement, dated as of February 6, 2013, by and among the Borrower, the lenders party thereto from time to time (the “Lenders”) and GCF, as Agent (in such capacity, together with its successors and assigns, the “Agent”) (as amended, restated, supplemented or otherwise modified from time to time, the “Existing Credit Agreement”) to facilitate the Borrower’s acquisition of all of the outstanding equity interests of each of Aeroflex / Inmet, Inc. and Aeroflex / Weinschel, Inc., each a Michigan corporation (collectively, the “Target” and, together with their respective subsidiaries, the “Acquired Business”), directly or through an affiliate (the “Acquisition”). The date on which the funding of the Amendment No. 3 Incremental Term Loan and the consummation of the Acquisition occurs shall be referred to herein as the “Closing Date”.

In connection with the foregoing, it is agreed that GCF will act as (i) sole lead arranger and bookrunner with respect to the Amendment No. 3 Incremental Term Loan and (ii) sole administrative agent and collateral agent with respect to the Amendment No. 3 Incremental Term Loan. It is further agreed that GCF shall have “left” placement in any and all marketing materials or other documentation used in connection with the Amendment No. 3 Incremental Term Loan (if any) and that no other agents, arrangers, or bookrunners will be appointed, no other titles will be awarded and no compensation (other than as expressly contemplated by this Commitment Letter and the Fee Letter (as defined below)) will be paid to any other party in order to obtain such party’s commitment to participate in the Amendment No. 3 Incremental Term Loan unless you and we shall so agree.

Section 1. Conditions Precedent.

Each Commitment Party’s several (and not joint) commitments to fund the Amendment No. 3 Incremental Term Loan and the borrowing of the Amendment No. 3 Incremental Term Loan is subject to

the following, it being understood that there are no conditions (implied or otherwise) to the commitments hereunder other than the conditions listed below (and upon satisfaction or waiver of such conditions, the Amendment No. 3 Incremental Term Loan shall be funded):

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Section 2. Commitment Termination.

GCF’s and each Commitment Party’s commitment and the obligations of each such party set forth in this Commitment Letter will terminate on the earliest to occur of (a) July 15, 2015, (b) the date the Operative Documents become effective and (c) the termination of the Acquisition or expiration of the related acquisition agreement prior to the Closing Date.

Section 3. Indemnification

The Borrower shall indemnify and hold harmless GCF and each Commitment Party and their respective affiliates and related funds and each of their respective officers, directors, employees, agents, advisors,

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attorneys and representatives (each, an “Indemnified Party”) from and against any and all claims, damages, losses, liabilities and expenses (including, without limitation, reasonable fees and disbursements of counsel), joint or several, that may be incurred by or asserted or awarded against any Indemnified Party (including, without limitation, in connection with or relating to any investigation, litigation or proceeding, actual or threatened, or the preparation of a defense in connection therewith), in each case arising out of or in connection with or by reason of this Commitment Letter, the Amendment No. 3 Incremental Term Loan or the Operative Documents, or any transactions or related transactions contemplated hereby or thereby, provided that the foregoing indemnity will not, as to any Indemnified Party, apply to claims, damages, losses, liabilities or expenses (i) to the extent they are found by a final, non-appealable judgment of by a court of competent jurisdiction to have resulted solely from such Indemnified Party’s gross negligence or willful misconduct, (ii) resulting from a material breach by such Indemnified Person of its express funding obligations under this Commitment Letter or (iii) resulting from any claim, litigation, investigation or proceeding solely between or among Indemnified Persons not arising from any act or omission by the Borrower or any of its affiliates (other than proceedings against GCF or any Commitment Party solely in its capacity as an agent or similar role). In the case of an investigation, litigation or other proceeding to which the indemnity in this paragraph applies, such indemnity shall be effective whether or not such investigation, litigation or proceeding is brought by the Borrower, any of its directors, security holders or creditors, an Indemnified Party or any other person, or an Indemnified Party is otherwise a party thereto and whether or not the transactions contemplated hereby or by the Operative Documents are consummated.

In no event shall any Indemnified Party be liable on any theory of liability for any special, indirect, consequential or punitive damages (including, without limitation, any loss of profits, business or anticipated savings).

Section 4. Costs and Expenses.

The Borrower shall pay, or reimburse GCF on demand for, all reasonable out-of-pocket costs and expenses incurred by GCF (whether incurred before or after the date hereof) in connection with the Amendment No. 3 Incremental Term Loan and the preparation, negotiation, execution and delivery of this Commitment Letter, the Fee Letter and the Operative Documents, including, without limitation, reasonable fees and expenses of one firm counsel and one local or specialist counsel, as necessary, in each appropriate jurisdiction or specialty, as applicable, regardless of whether any of the transactions contemplated hereby is consummated.

Section 5. Confidentiality.

By accepting delivery of this Commitment Letter, the Borrower agrees that this Commitment Letter and the Fee Letter are for its confidential use and that neither their existence nor the terms thereof will be disclosed by it to any person except (a) its officers, directors, employees, affiliates, accountants, attorneys and other advisors (the “Representatives”), in each case only on a confidential and “need to know” basis in connection with the transactions contemplated hereby, (b) the contents of this Commitment Letter and the Fee Letter (provided, that any disclosure of the Fee Letter or its terms or substance under this clause (b) shall be redacted in a manner reasonably satisfactory to GCF) may be disclosed to the Target and its Representatives on a confidential and “need to know” basis in connection with the transactions contemplated hereby, (c) this Commitment Letter (but not the Fee Letter) may be disclosed (i) to the extent required by the applicable rules of any national securities exchange and/or (ii) to the extent required by applicable federal securities laws, in connection with any Securities and Exchange Commission filings or any other required public filings relating to the Acquisition; (d) in connection with the exercise of any remedy or enforcement of any right under this Commitment Letter; and (e) the aggregate fee amount may be disclosed in financial statements; provided, however, that the Borrower may

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disclose the existence and terms hereof to the extent required by applicable law or in connection with any subpoena or litigation or to the extent that such existence or terms becomes public knowledge by a reason other than breach by the Borrower or any of its Representatives. The provisions of this paragraph shall automatically terminate (except with respect to the Fee Letter) on the date that is one year following the date hereof.

Each of GCF and each Commitment Parties individually (and not jointly or jointly and severally) agrees to use all material, nonpublic information received by them in connection with the transactions contemplated hereby solely for the purposes of providing the services that are the subject of this Commitment Letter and shall treat confidentially all such information; provided, however, that nothing herein shall prevent GCF or the Commitment Parties from disclosing any such information (a) to any Lenders or participants or prospective Lenders or participants; (b) as may be required by statute, decision, or judicial or administrative order, rule, or regulation; provided that (x) prior to any disclosure under this clause (b), the disclosing party agrees to provide the Borrower with prior notice thereof, to the extent that it is practicable to do so and to the extent that the disclosing party is permitted to provide such prior notice to Borrower pursuant to the terms of the applicable statute, decision, or judicial or administrative order, rule, or regulation and (y) any disclosure under this clause (b) shall be limited to the portion of the such confidential information as may be required by such statute, decision, or judicial or administrative order, rule, or regulation; (c) as may be required by regulatory authorities so long as such authorities are informed of the confidential nature of such information; (d) as may be agreed to in advance in writing by the Borrower; (e) to GCF’s or any Commitment Party’s Representatives or GCF’s or any Commitment Party’s respective affiliates’ Representatives on a need-to-know basis who are informed of the confidential nature of such information and are or have been advised of their obligation to keep information of this type confidential; (f) as requested or required by any Governmental Authority (as defined in the Existing Credit Agreement) pursuant to any subpoena or other legal process, provided, that, (x) prior to any disclosure under this clause (f) the disclosing party agrees to provide Borrower with prior written notice thereof, to the extent that it is practicable to do so and to the extent that the disclosing party is permitted to provide such prior written notice to Borrower pursuant to the terms of the subpoena or other legal process and (y) any disclosure under this clause (f) shall be limited to the portion of the confidential information as may be required by such Governmental Authority pursuant to such subpoena or other legal process; (g) to the extent any such information is or becomes publicly available other than by reason of disclosure by the relevant disclosing party or its respective Representatives in breach of this paragraph; and (h) in connection with the exercise of any remedy or enforcement of any right under this Commitment Letter or the Fee Letter; provided that the disclosure of any such information to any Lenders or prospective Lenders or participants or prospective participants referred to above shall be made subject to the acknowledgment and acceptance by such Lender or prospective Lender or participant or prospective participant that such information is being disseminated on a confidential basis (and they shall agree to be bound to substantially the same terms as are set forth in this paragraph or as are otherwise reasonably acceptable to the Borrower and GCF). The provisions of this paragraph shall automatically terminate on the earlier of (x) the Closing Date and (y) the date that is one year following the date hereof.

Section 6. Representations and Warranties.

The Borrower hereby represents and warrants that (a) all written information that has been or will hereafter be made available to GCF or any Commitment Party by it or any of its Representatives in connection with the transactions contemplated hereby (other than financial projections or forward-looking information and information of a general economic or industry-specific nature), taken as a whole together with the Borrower’s filings with the Securities and Exchange Commission, is and will be complete and correct in all material respects and does not and will not contain any untrue statement of a material fact or omit to state a material fact necessary in order to make the statements contained therein not misleading in any material respect in light of the circumstances under which such statements were or are made and (b)

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all financial projections, if any, that have been or will be prepared by it or its Representatives and made available to GCF or any Commitment Party have been or will be prepared in good faith based upon assumptions that the Borrower believed were reasonable as of the date of the preparation of such financial projections (it being understood that such projections are subject to uncertainties and contingencies and that no assurance can be given that the projections will be realized) and at the time disclosed to GCF or such Commitment Party. The Borrower agrees to make such disclosures relating to events or developments and to revise any such projections until the Operative Documents become effective so that the representations and warranties contained in this paragraph remain correct in all material respects and not misleading in any material respect as specified in this Section 6.

In providing this Commitment Letter, GCF and the Commitment Parties will be entitled to use, and is relying on the accuracy of, the information furnished to it by or on behalf of the Borrower and its Representatives without independent verification thereof.

Section 7. No Third Party Reliance, Etc.

The agreements of GCF and the Commitment Parties hereunder are made solely for the benefit of the Borrower and may not be relied upon or enforced by any other person. Please note that those matters that are not covered or made clear in this Commitment Letter are subject to mutual agreement of the parties. The Borrower may not assign or delegate any of its rights or obligations hereunder without the GCF’s and Commitment Parties’ prior written consent. This Commitment Letter may not be amended or modified, or any provisions hereof waived, except by a written agreement signed by all parties hereto.

You acknowledge that GCF, the Commitment Parties and their respective affiliates and other accounts managed by affiliates of GCF may be providing debt financing, equity capital or other services (including, without limitation, financial advisory services) to other companies in respect of which you may have conflicting interests or a commercial or competitive relationship with and otherwise. Neither GCF, the Commitment Parties nor their respective affiliates will use confidential information obtained from you by virtue of the transactions contemplated by this Commitment Letter or their other relationships with you in connection with the performance by GCF, the Commitment Parties or their respective affiliates of services for other companies, and neither GCF, the Commitment Parties nor their respective affiliates will furnish any such information to other companies. You acknowledge and agree that (a) the transactions contemplated by this Commitment Letter are arm’s-length commercial transactions between the Commitment Parties and GCF, on the one hand, and the Borrower, on the other, (b) in connection therewith and with the process leading to such transaction each Commitment Party and GCF is acting solely as a principal and not as agents or fiduciaries of you, your management, shareholders, creditors or any other person, (c) the Commitment Parties have not assumed an advisory or fiduciary responsibility or any other obligation in favor of you with respect to the transactions contemplated hereby or the process leading thereto (irrespective of whether the Commitment Parties or any of their respective affiliates have advised or are currently advising you on other matters) except the obligations expressly set forth in this Commitment Letter and (d) you have consulted your own legal, tax, accounting and financial advisors to the extent you deemed appropriate. You further acknowledge and agree that you are responsible for making your own independent judgment with respect to such transactions and the process leading thereto. Please note that the Commitment Parties, GCF and their respective affiliates have not provided any legal, accounting, regulatory or tax advice. In addition, you acknowledge that GCF currently is acting as Agent under the Existing Credit Agreement, and one or more of the Commitment Parties or their affiliates may be acting as lenders, under the Existing Credit Agreement, and your and your affiliates’ rights and obligations under such agreements or any other agreement with the Commitment Parties that may currently or hereafter exist are, and shall be, separate and distinct from the rights and obligations of the parties pursuant to this Commitment Letter, and none of such rights and obligations under the Existing Credit Agreement or such other agreements shall be

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affected by the Commitment Parties’ or GCF’s performance or lack of performance of services hereunder. You hereby agree that each Commitment Party may render its services under this Commitment Letter notwithstanding any actual or potential conflict of interest presented by the foregoing, and you hereby waive any conflict of interest claims relating to the relationship between any Commitment Party or GCF and the Borrower and its affiliates in connection with the services contemplated hereby, on the one hand, and the exercise by any Commitment Party or GCF or any of their affiliates of any of their rights and duties under any credit or other agreement (including the under the Existing Credit Agreement), on the other hand.

Section 8. Governing Law, Etc.

This Commitment Letter will be governed by and construed in accordance with the laws of the State of New York without regard to conflict of law principles that would result in the application of any law other than the law of the State of New York. This Commitment Letter is intended to be solely for the benefit of the parties hereto and is not intended to confer any benefits upon, or create any rights in favor of, any person other than the parties hereto. This Commitment Letter may be executed in any number of counterparts, each of which shall be deemed an original, and all of which, when taken together, shall constitute one agreement. Delivery of an executed counterpart of a signature page of this Commitment Letter by facsimile transmission or other electronic transmission (i.e., a “pdf” or “tiff”) shall be effective as delivery of a manually executed counterpart hereof. Sections 3, 4, 5, 7, 8 and 9 hereof shall survive the termination of this Commitment Letter.

Section 9. Waiver of Jury Trial, Etc.

Each party hereto irrevocably waives all right to trial by jury in any action, proceeding or counterclaim (whether based on contract, tort or otherwise) arising out of or relating to this Commitment Letter or the transactions contemplated hereby or the actions of the parties hereto in the negotiation, performance or enforcement hereof.

With respect to all matters relating to this Commitment Letter, including Exhibit A, the Borrower irrevocably (a) submits to the exclusive jurisdiction of any New York State or federal court sitting in the State of New York, County of New York, and any appellate court from any thereof, (b) agrees that all claims related hereto may be heard and determined in such courts, (c) waives, to the fullest extent it may effectively do so, the defense of an inconvenient forum, (d) agrees that a final judgment of such courts shall be conclusive and may be enforced in other jurisdictions by suit on the judgment or in any other manner provided by law, (e) waives any immunity from jurisdiction of any court or from any legal process or setoff to which it or its properties or assets may be entitled and (f) consents to the service of any and all process with respect to all matters relating to this Commitment Letter by any manner permitted by law.

Any and all obligations of, and services to be provided by GCF or the Commitment Parties hereunder may be performed and any and all rights of GCF and the Commitment Parties hereunder may be exercised by or through any of its respective affiliates or branches and, in connection with such performance or exercise, the Commitment Parties may exchange with such affiliates or branches information concerning you and your affiliates that may be the subject of the transactions contemplated hereby and, to the extent so employed, such affiliates and branches shall be entitled to the benefits afforded to GCF and the Commitment Parties hereunder.

Please indicate the Borrower’s acceptance of the provisions hereof by signing the enclosed copy of this Commitment Letter and the related Fee Letter and returning each such document at or before 8:00 p.m. (New York City time) on April 23, 2015, the time at which the commitment of GCF and the Commitment

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Parties set forth above (if not received on or prior thereto) will terminate. If the Borrower elects to deliver this Commitment Letter and Fee Letter by electronic communication, please arrange for the executed original to follow by next-day courier.

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[SIGNATURE PAGE TO COMMITMENT LETTER]

[SIGNATURE PAGE TO COMMITMENT LETTER]

Accepted and agreed to as of

the date first above written:

[SIGNATURE PAGE TO COMMITMENT LETTER]

Schedule I

Amendment No. 3 Incremental Term Loan

Exhibit A¹

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3

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Annex I

Interest Coverage Ratio:

Leverage Ratio: