Exhibit 10.7


 


UNIT
SUBSCRIPTION AGREEMENT


 


This UNIT SUBSCRIPTION
AGREEMENT (this “Agreement”) is made, effective as of April 19, 2017, by and between KBL Merger Corp. IV, a
Delaware corporation (the “Company”), with a principal place of business at 527 Stanton Christiana Rd, Newark,
DE 19713, and the purchasers listed on Schedule A attached to this Agreement (each, a “Subscriber” and
collectively, the “Subscribers”).


 


WHEREAS, the Company
desires to sell to the Subscribers on a private placement basis (the “Offering”) up to that number of Units
set forth on Schedule A, which shall amount to an aggregate of 100,000 units (the “Initial Units”) of the Company,
and up to an additional 15,000 units (the “Additional Units” and together with the Initial Units, the “Units”)
of the Company in the event that the underwriters’ 45-day over-allotment option (“Over-Allotment Option”)
is exercised in full or part, each Unit comprised of one share of common stock of the Company, par value $0.0001 per share (“Common
Stock”), and one warrant to purchase one full share of Common Stock (“Warrant”), for the purchase
prices set forth on Schedule A, which shall amount to an aggregate purchase price of $1,000,000 (or up to $1,115,000 if the Over-Allotment
Option is exercised in full), or $10.00 per Unit. The shares of Common Stock underlying the Warrants are hereinafter referred to
as the “Warrant Shares.”  The shares of Common Stock underlying the Units (excluding the Warrant Shares)
are hereinafter referred to as the “Placement Shares.” The Warrants underlying the Units are hereinafter referred
to as the “Placement Warrants.”  The Units, Placement Shares, Placement Warrants and Warrant Shares,
collectively, are hereinafter referred to as the “Securities.”  Each Placement Warrant is exercisable
to purchase one full share of Common Stock at an exercise price of $11.50 per whole share during the period commencing on the later
of (i) twelve (12) months from the date of the closing of the Company’s initial public offering of units (the “IPO”)
and (ii) 30 days following the consummation of the Company’s initial business combination (the “Business Combination”),
as such term is defined in the registration statement in connection with the IPO, as amended at the time it becomes effective (the
“Registration Statement”), and expiring on the fifth anniversary of the consummation of the Business Combination;
and


  


NOW, THEREFORE,
in consideration of the premises and the mutual covenants hereinafter set forth and other good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, the Company and Subscriber hereby agree as follows:


 


1.     Agreement
to Subscribe


 


		1.1.	Purchase and Issuance of the Units.



 


		1.1.1.	Upon the terms and subject to the conditions of this Agreement, the Subscribers hereby agree to
purchase from the Company, and the Company hereby agrees to sell to the Subscribers, on the initial Closing Date (as defined below)
the Initial Units in consideration of the payment of the Initial Purchase Price (as defined below) in accordance with Schedule
A. On the initial Closing Date, or within a reasonable time after the initial Closing Date, but in no event later than thirty (30)
days after the initial Closing Date, the Company shall deliver to the Subscribers the certificates representing the Securities
purchased.



 


		1.1.2.	Subscribers hereby agree to purchase up to an additional 15,000 Additional Units at $10.00 per
Additional Unit for a purchase price of up to $150,000. The purchase and issuance of the Additional Units shall occur only in the
event that the Over-Allotment Option is exercised in full or in part. The total number of Additional Units to be purchased hereunder
shall be in the same proportion as the proportion of the Over-Allotment Option that is exercised. Each purchase of Additional Units
shall occur simultaneously with the consummation of any portion of the Over-Allotment Option.



  


		1.2.	Purchase Price. 



 


		1.2.1.	As payment in full for the Initial Units being purchased under this Agreement, each Subscriber
shall pay their respective purchase price set forth on Schedule A, which shall amount to an aggregate purchase price of $1,000,000
(the “Initial Purchase Price”), by wire transfer of immediately available funds or by such other method as may
be reasonably acceptable to the Company, to the trust account (the “Trust Account”) at a financial institution
to be chosen by the Company, maintained by Continental Stock Transfer & Trust Company, acting as trustee (“Continental”),
on the Closing Date of the IPO.



 


		1.2.2.	As payment in full for the Additional Units being purchased under this Agreement, the Subscribers
shall pay $10.00 per Additional Unit being purchased by wire transfer of immediately available funds or by such other method as
may be reasonably acceptable to the Company, to the Trust Account at a financial institution to be chosen by the Company, maintained
by Continental, on the Closing Date of the Over-Allotment Option.



 



    


     

    




        1.3.   
Closings. The closing of the purchase and sale of the Initial Units shall take place simultaneously with the closing of the IPO
and the closing of the purchase and sale of Additional Units shall take place simultaneously with the closing of the Over-Allotment
Option (each a “Closing Date”). The closing of the purchase and sale of the Units shall take place at the offices
of Holland & Knight LLP, 31 W 52nd St., New York, New York, 10019, or such other place as may be agreed upon by
the parties hereto.


 


1.4      Termination.
This Agreement and each of the obligations of the undersigned shall be null and void and without effect if a Closing does not occur
prior to June 30, 2017.


  


2.     Representations
and Warranties of Subscribers


 


Subscribers each
represent and warrant to the Company that:


 


2.1.  
 No Government Recommendation or Approval.  Subscriber understands that no federal or state agency has passed upon
or made any recommendation or endorsement of the Company or the Offering of the Securities.


 


2.2.   
Accredited Investor. Subscriber represents that it is an “accredited investor” as such term is defined in Rule 501(a)
of Regulation D under the Securities Act of 1933, as amended (the “Securities Act”), and acknowledges that the
sale contemplated hereby is being made in reliance, among other things, on a private placement exemption to “accredited investors”
under the Securities Act and similar exemptions under state law.


 


2.3.   
Intent. Subscriber is purchasing the Securities solely for investment purposes, for such Subscriber’s own account and not
with a view to the distribution thereof and Subscriber has no present arrangement to sell the Securities to or through any person
or entity. Subscriber shall not engage in hedging transactions with regard to the Securities unless in compliance with the Securities
Act.


  


2.4.   
Restrictions on Transfer.  Subscriber acknowledges and understands the Units are being offered in a transaction not
involving a public offering in the United States within the meaning of the Securities Act.  The Securities have not
been registered under the Securities Act and, if in the future Subscriber decides to offer, resell, pledge or otherwise transfer
the Securities, such Securities may be offered, resold, pledged or otherwise transferred only (A) pursuant to an effective
registration statement filed under the Securities Act, (B) pursuant to an exemption from registration under Rule 144 promulgated
under the Securities Act, if available, or (C) pursuant to any other available exemption from the registration requirements
of the Securities Act, and in each case in accordance with any applicable securities laws of any state or any other jurisdiction.
Notwithstanding the foregoing, Subscriber acknowledges and understands the Securities are subject to transfer restrictions as
described in Section 8 hereof. Subscriber agrees that if any transfer of its Securities or any interest therein is proposed to
be made, as a condition precedent to any such transfer, Subscriber may be required to deliver to the Company an opinion of counsel
satisfactory to the Company with respect to such transfer. Absent registration or another available exemption from registration,
Subscriber agrees it will not resell the Securities (unless otherwise permitted herein, as described in the Registration Statement).  Subscriber
further acknowledges that because the Company is a shell company, Rule 144 may not be available to Subscriber for the resale of
the Securities until the one year anniversary following consummation of the initial Business Combination of the Company, despite
technical compliance with the requirements of Rule 144 and the release or waiver of any contractual transfer restrictions.


 



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2.5.  Sophisticated
Investor.


 


(i)  Subscriber
is sophisticated in financial matters and is able to evaluate the risks and benefits of the investment in the Securities.


 


(ii) Subscriber
is aware that an investment in the Securities is highly speculative and subject to substantial risks because, among other things,
the Securities are subject to transfer restrictions and have not been registered under the Securities Act and therefore cannot
be sold unless subsequently registered under the Securities Act or an exemption from such registration is available. Subscriber
is able to bear the economic risk of its investment in the Securities for an indefinite period of time.


 


2.6.   Independent
Investigation.  Subscriber, in making the decision to purchase the Units, has relied upon an independent investigation
of the Company and has not relied upon any information or representations made by any third parties or upon any oral or written
representations or assurances from the Company, its officers, directors or employees or any other representatives or agents of
the Company, other than as set forth in this Agreement. Subscriber is familiar with the business, operations and financial condition
of the Company and has had an opportunity to ask questions of, and receive answers from the Company’s officers and directors
concerning the Company and the terms and conditions of the offering of the Units and has had full access to such other information
concerning the Company as Subscriber has requested. Subscriber confirms that all documents that it has requested have been made
available and that Subscriber has been supplied with all of the additional information concerning this investment which Subscriber
has requested.


 


2.7   Organization
and Authority.  Subscriber is duly organized, validly existing and in good standing under the laws of the State of Delaware
and it possesses all requisite power and authority necessary to carry out the transactions contemplated by this Agreement.


 


2.8.  Authority.
This Agreement has been validly authorized, executed and delivered by Subscriber and is a valid and binding agreement enforceable
in accordance with its terms, subject to the general principles of equity and to bankruptcy or other laws affecting the enforcement
of creditors’ rights generally.


  


2.9.   
No Conflicts. The execution, delivery and performance of this Agreement and the consummation by Subscriber of the transactions
contemplated hereby do not violate, conflict with or constitute a default under (i) Subscriber's charter documents, (ii) any
agreement or instrument to which Subscriber is a party or (iii) any law, statute, rule or regulation to which Subscriber is subject,
or any agreement, order, judgment or decree to which Subscriber is subject except as would not have a material adverse effect on
Subscriber’s purchase hereunder.


 


2.10.  No Legal
Advice from Company.  Subscriber acknowledges it has had the opportunity to review this Agreement and the transactions
contemplated by this Agreement and the other agreements entered into between the parties hereto with Subscriber’s own legal
counsel and investment and tax advisors.  Except for any statements or representations of the Company made in this Agreement
and the other agreements entered into between the parties hereto, Subscriber is relying solely on such counsel and advisors and
not on any statements or representations of the Company or any of its representatives or agents for legal, tax or investment advice
with respect to this investment, the transactions contemplated by this Agreement or the securities laws of any jurisdiction.


 


2.11.  Reliance
on Representations and Warranties.  Subscriber understands the Units are being offered and sold to Subscriber in reliance
on exemptions from the registration requirements under the Securities Act, and analogous provisions in the laws and regulations
of various states, and that the Company is relying upon the truth and accuracy of the representations, warranties, agreements,
acknowledgments and understandings of Subscriber set forth in this Agreement in order to determine the applicability of such provisions.


 


2.12.  No General
Solicitation.  Subscriber is not subscribing for the Units as a result of or subsequent to any general solicitation or
general advertising, including but not limited to any advertisement, article, notice or other communication published in any newspaper,
magazine, or similar media or broadcast over television or radio, or presented at any seminar or meeting or in a registration statement
with respect to the IPO filed with the Securities and Exchange Commission (“SEC”).


 



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2.13.  Legend.  Subscriber
acknowledges and agrees the certificates evidencing each of the Securities shall bear a restrictive legend (the “Legend”),
in form and substance substantially as set forth in Section 4 hereof.


 


3.    Representations,
Warranties and Covenants of the Company


 


The Company represents
and warrants to, and agrees with, each Subscriber that:


 


3.1.   
Valid Issuance of Capital Stock. The total number of shares of all classes of capital stock which the Company has authority to
issue is 35,000,000 shares of Common Stock and 1,000,000 shares of preferred stock, $0.0001 par value per share (“Preferred
Stock”). As of the date hereof, the Company has issued and outstanding 2,875,000 shares of Common Stock (of which up
to 375,000 shares are subject to forfeiture as described in the Registration Statement) and no shares of Preferred Stock. All of
the issued shares of capital stock of the Company have been duly authorized, validly issued, and are fully paid and non-assessable.


 


3.2    
Title to Securities.  Upon issuance in accordance with, and payment pursuant to, the terms hereof and that certain warrant
agreement to be entered into between the Company and Continental, as warrant agent (the “Warrant Agreement”),
as the case may be, each of the Units, Placement Shares, Placement Warrants and the Warrant Shares will be duly and validly issued,
fully paid and non-assessable. On the date of issuance of the Units, the Warrant Shares shall have been reserved for issuance.
Upon issuance in accordance with, and payment pursuant to, the terms hereof and the Warrant Agreement, as the case may be, Subscriber
will have or receive good title to the Units, Placement Shares and Placement Warrants, free and clear of all liens, claims and
encumbrances of any kind, other than (i) transfer restrictions hereunder and (ii) transfer restrictions under federal and state
securities laws.


  


3.3.   
Organization and Qualification. The Company is a corporation duly incorporated, validly existing and in good standing under the
laws of the State of Delaware and has the requisite corporate power to own its properties and assets and to carry on its business
as now being conducted.


 


3.4.   
Authorization; Enforcement. (i) The Company has the requisite corporate power and authority to enter into and perform its
obligations under this Agreement and to issue the Securities in accordance with the terms hereof, (ii) the execution, delivery
and performance of this Agreement by the Company and the consummation by it of the transactions contemplated hereby have been duly
authorized by all necessary corporate action, and no further consent or authorization of the Company or its Board of Directors
or stockholders is required, and (iii) this Agreement constitutes valid and binding obligations of the Company enforceable
against the Company in accordance with its terms, except as such enforceability may be limited by applicable bankruptcy, insolvency,
fraudulent conveyance, moratorium, reorganization, or similar laws relating to, or affecting generally the enforcement of, creditors’
rights and remedies or by equitable principles of general application and except as enforcement of rights to indemnity and contribution
may be limited by federal and state securities laws or principles of public policy.


 


3.5.   
No Conflicts. The execution, delivery and performance of this Agreement and the consummation by the Company of the transactions
contemplated hereby do not (i) result in a violation of the Company’s certificate of incorporation or by-laws, (ii) conflict
with, or constitute a default under any agreement or instrument to which the Company is a party or (iii) any law statute, rule
or regulation to which the Company is subject or any agreement, order, judgment or decree to which the Company is subject. Other
than any SEC or state securities filings which may be required to be made by the Company subsequent to the Closing, and any registration
statement which may be filed pursuant thereto, the Company is not required under federal, state or local law, rule or regulation
to obtain any consent, authorization or order of, or make any filing or registration with, any court or governmental agency or
self-regulatory entity in order for it to perform any of its obligations under this Agreement or issue the Units, Placement Shares,
Warrants or the Warrant Shares in accordance with the terms hereof.


 



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4.     Legends


 


4.1.    Legend.
The Company will issue the Units, Placement Shares and Warrants, and when issued, the Warrant Shares, purchased by the Subscriber
in the name of the Subscriber. The Securities will bear the following Legend and appropriate “stop transfer” instructions:


 


“THE
SECURITIES REPRESENTED HEREBY HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “SECURITIES ACT”),
OR ANY STATE SECURITIES LAWS AND NEITHER THE SECURITIES NOR ANY INTEREST THEREIN MAY BE OFFERED, SOLD, TRANSFERRED, PLEDGED OR
OTHERWISE DISPOSED OF EXCEPT PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER THE SECURITIES ACT OR SUCH LAWS OR AN EXEMPTION
FROM REGISTRATION UNDER THE SECURITIES ACT AND SUCH LAWS WHICH, IN THE OPINION OF COUNSEL FOR THIS CORPORATION, IS AVAILABLE.”


 


“THE
SECURITIES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO LOCKUP PURSUANT TO A UNIT PURCHASE AGREEMENT BY AND BETWEEN KBL MERGER
CORP. IV, AND LADENBURG THALMANN & CO. INC., B. RILEY & CO., LLC AND FBR CAPITAL MARKETS & CO. AND MAY ONLY BE OFFERED,
SOLD, TRANSFERRED, PLEDGED OR OTHERWISE DISPOSED DURING THE TERM OF THE LOCKUP PURSUANT TO THE TERMS SET FORTH IN THE UNIT PURCHASE
AGREEMENT.”


  


4.2.   
Subscriber’s Compliance. Nothing in this Section 4 shall affect in any way Subscriber’s obligations and agreements
to comply with all applicable securities laws upon resale of the Securities.


 


4.3.   
Company’s Refusal to Register Transfer of the Securities.  The Company shall refuse to register any transfer of
the Securities, if in the sole judgment of the Company such purported transfer would not be made (i) pursuant to an effective
registration statement filed under the Securities Act, or pursuant to an available exemption from the registration requirements
of the Securities Act and (ii) in compliance herewith.


 


4.4    
Registration Rights. Subscriber will be entitled to certain registration rights which will be governed by a registration rights
agreement (“Registration Rights Agreement”) to be entered into between, among others, Subscriber and the Company,
on or prior to the effective date of the Registration Statement; provided, however, that the Subscriber may not exercise its demand
and “piggy back” registration rights pursuant to such Registration Rights Agreement after five (5) and seven (7) years
after the effective date of the Registration Statement, respectively, and the Subscriber may not exercise its demand registration
rights thereunder more than one time.


 


5.    Lockup.


 


The Subscriber
acknowledges and agrees that the Units, the Placement Shares, the Warrants and the Warrant Shares shall not be transferable, saleable
or assignable until 30 days after the consummation of a Business Combination, except to permitted transferees. The Units, the
Placement Shares, the Warrants and the Warrant Shares will be deemed compensation by the Financial Industry Regulatory Authority
(“FINRA”) and will therefore be subject to lock-up for a period of 180 days immediately following the date of effectiveness
of the Registration Statement or commencement of sales of the IPO, subject to certain limited exceptions, pursuant to Rule 5110(g)(1)
of the FINRA Manual. Accordingly, the Units, the Placement Shares, the Warrants and the Warrant Shares may not be sold, transferred,
assigned, pledged or hypothecated for 180 days immediately following the effective date of the Registration Statement except to
any underwriter or selected dealer participating in the IPO and the bona fide officers or partners of the Subscriber and any such
participating underwriter or selected dealer nor may they be the subject of any hedging, short sale, derivative, put or call transaction
that would result in the economic disposition of the securities by any person during such 180-day period.


 



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6.       Waiver
of Liquidation Distributions.


 


In connection with
the Securities purchased pursuant to this Agreement, Subscriber hereby waives any and all right, title, interest or claim of any
kind in or to any distributions of the amounts in the Trust Account with respect to the Securities, whether (i) in connection with
the exercise of redemption rights if the Company consummates the Business Combination, (ii) in connection with any tender offer
conducted by the Company prior to a Business Combination or (iii) upon the Company’s redemption of shares of Common Stock
sold in the Company’s IPO upon the Company’s failure to timely complete the Business Combination.  In the
event Subscriber purchases shares of Common Stock in the IPO or in the aftermarket, any additional shares so purchased shall be
eligible to receive the redemption value of such shares of Common Stock upon the same terms offered to all other purchasers of
Common Stock in the IPO in the event the Company fails to consummate the Business Combination.


 


7.     Termination
of Placement Warrants.


 


7.1.   
Failure to Consummate Business Combination. The Placement Warrants shall be terminated upon the dissolution of the Company or in
the event that the Company does not consummate the Business Combination within 24 months from the consummation of the IPO, unless
otherwise extended by the Corporation.


 


7.2.   
Termination of Rights as Holder. If the Placement Warrants are terminated in accordance with Section 7.1, then after such
time Subscriber (or successor in interest) shall no longer have any rights as a holder of such Placement Warrants and the Company
shall take such action as is appropriate to cancel such Placement Warrants. Subscriber hereby irrevocably grants the Company a
limited power of attorney for the purpose of effectuating the foregoing and agrees to take any and all measures reasonably requested
by the Company necessary to effect the foregoing.


 


8.     Rescission
Right Waiver and Indemnification.


 


8.1.   
Subscriber understands and acknowledges an exemption from the registration requirements of the Securities Act requires there be
no general solicitation of purchasers of the Units. In this regard, if the IPO were deemed to be a general solicitation with respect
to the Units, the offer and sale of such Units may not be exempt from registration and, if not, Subscriber may have a right to
rescind its purchase of the Units. In order to facilitate the completion of the Offering and in order to protect the Company, its
stockholders and the amounts in the Trust Account from claims that may adversely affect the Company or the interests of its stockholders,
Subscriber hereby agrees to waive, to the maximum extent permitted by applicable law, any claims, right to sue or rights in law
or arbitration, as the case may be, to seek rescission of its purchase of the Units. Subscriber acknowledges and agrees this waiver
is being made in order to induce the Company to sell the Units to the Subscriber. Subscriber agrees the foregoing waiver of rescission
rights shall apply to any and all known or unknown actions, causes of action, suits, claims or proceedings (collectively, “Claims”)
and related losses, costs, penalties, fees, liabilities and damages, whether compensatory, consequential or exemplary, and expenses
in connection therewith, including reasonable attorneys’ and expert witness fees and disbursements and all other expenses
reasonably incurred in investigating, preparing or defending against any Claims, whether pending or threatened, in connection with
any present or future actual or asserted right to rescind the purchase of the Units hereunder or relating to the purchase of the
Units and the transactions contemplated hereby.


 


8.2.     Subscriber
agrees not to seek recourse against the Trust Account for any reason whatsoever in connection with its purchase of the Units or
any Claim that may arise now or in the future relating to the purchase of the Units.


 


8.3.   
Subscriber acknowledges and agrees that the stockholders of the Company are and shall be third-party beneficiaries of this Section
8. 


 


8.4.   
Subscriber agrees that to the extent any waiver of rights under this Section 8 is ineffective as a matter of law, Subscriber has
offered such waiver for the benefit of the Company as an equitable right that shall survive any statutory disqualification or bar
that applies to a legal right. Subscriber acknowledges the receipt and sufficiency of consideration received from the Company hereunder
in this regard.


 



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9.     Terms
of the Units and Underlying Securities


 


9.1. The Units and
their component parts are substantially identical to the units to be offered in the IPO except that: (i) the Units and component
parts will be subject to transfer restrictions, except in limited circumstances, until 30 days following the consummation of the
Business Combination, (ii) the Placement Warrants will be non-redeemable so long as they are held by the initial holder thereof
(or any of its permitted transferees), and may be exercisable on a “cashless” basis if held by Subscriber or its
permitted transferees and (iii) the Units and component parts are being purchased pursuant to an exemption from the registration
requirements of the Securities Act and will become freely tradable only after the expiration of the lockup described above in clause
(i) and they are registered pursuant to the Registration Rights Agreement to be signed on or before the date of the Prospectus
or an exemption from registration is available. Additionally, so long as the Placement Warrants are held by the Subscriber or its
designees, they will not be permitted to exercise such Placement Warrants after the five year anniversary of the effective date
of the Registration Statement.


 


10.        Governing
Law; Jurisdiction; Waiver of Jury Trial


 


This Agreement shall
be governed by and construed in accordance with the laws of the State of New York for agreements made and to be wholly performed
within such state. The parties hereto hereby waive any right to a jury trial in connection with any litigation pursuant to this
Agreement and the transactions contemplated hereby.


  


11.   Assignment;
Entire Agreement; Amendment


 


11.1.  Assignment.
Neither this Agreement nor any rights hereunder may be assigned by any party to any other person other than by Subscriber to a
person agreeing to be bound by the terms hereof, including the waiver contained in Section 8 hereof.


 


11.2.  Entire
Agreement. This Agreement sets forth the entire agreement and understanding between the parties as to the subject matter thereof
and merges and supersedes all prior discussions, agreements and understandings of any and every nature among them.


 


11.3.  Amendment.
Except as expressly provided in this Agreement, neither this Agreement nor any term hereof may be amended, waived, discharged or
terminated other than by a written instrument signed by the party against whom enforcement of any such amendment, waiver, discharge
or termination is sought.


 


11.4.  Binding
upon Successors. This Agreement shall be binding upon and inure to the benefit of the parties hereto and to their respective heirs,
legal representatives, successors and permitted assigns. 


  


12.   Notices


 


12.1  
Notices. Unless otherwise provided herein, any notice or other communication to a party hereunder shall be sufficiently given
if in writing and personally delivered or sent by facsimile or other electronic transmission with copy sent in another manner
herein provided or sent by courier (which for all purposes of this Agreement shall include Federal Express or other recognized
overnight courier) or mailed to said party by certified mail, return receipt requested, at its address provided for herein or
such other address as either may designate for itself in such notice to the other.  Communications shall be deemed to
have been received when delivered personally, on the scheduled arrival date when sent by next day or 2nd-day courier service,
or if sent by facsimile upon receipt of confirmation of transmittal or, if sent by mail, then three days after deposit in the
mail. If given by electronic transmission, such notice shall be deemed to be delivered (a) if by electronic mail, when directed
to an electronic mail address at which the stockholder has consented to receive notice; (b) if by a posting on an electronic
network together with separate notice to the stockholder of such specific posting, upon the later of (1) such posting and
(2) the giving of such separate notice; and (c) if by any other form of electronic transmission, when directed to the
stockholder.






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13.   Counterparts


 


This Agreement may
be executed in one or more counterparts, all of which when taken together shall be considered one and the same agreement and shall
become effective when counterparts have been signed by each party and delivered to the other party, it being understood that both
parties need not sign the same counterpart. In the event that any signature is delivered by facsimile transmission or by e-mail
delivery of a “pdf” format data file, such signature shall create a valid and binding obligation of the party executing
(or on whose behalf such signature is executed) with the same force and effect as if such facsimile or “.pdf” signature
page were an original thereof.


 


14.   Survival;
Severability


 


14.1.  Survival.
The representations, warranties, covenants and agreements of the parties hereto shall survive each Closing Date.


 


14.2. Severability.
In the event that any provision of this Agreement becomes or is declared by a court of competent jurisdiction to be illegal, unenforceable
or void, this Agreement shall continue in full force and effect without said provision; provided that no such severability shall
be effective if it materially changes the economic benefit of this Agreement to any party.


 


15.   Headings.


 


The titles and subtitles
used in this Agreement are used for convenience only and are not to be considered in construing or interpreting this Agreement.


 


[Signature Pages Follow]


 



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This subscription is accepted by the
Company on the 9th day of May, 2017.


 


	 	KBL MERGER CORP. IV
	 	 	 
	 	By:	 /s/ Marlene Krauss, M.D.
	 	 	Name:  Marlene Krauss, M.D.
	 	 	Title: Chief Executive Officer


 


Accepted and agreed on the date hereof:


 


	 	
        SUBSCRIBERS:

         

        LADENBURG THALMANN & CO. INC.

	 	 	 
	 	By:	 /s/ Steven Kaplan
	 	 	Name: Steven Kaplan 
	 	 	Title: Head of Capital Markets
	 	
         

B. RILEY & CO., LLC

	 	 	 
	 	By:	 /s/ Steve Reiner
	 	 	Name: Steve Reiner
	 	 	Title: Managing Director
	 	
        

        

        FBR CAPITAL MARKETS & CO.

	 	 	 
	 	By:	 /s/ Patrice McNicoll
	 	 	Name: Patrice McNicoll 
	 	 	Title: Co-Head of Capital Markets
	 	 	 


 












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SCHEDULE A


 


	Subscriber	Number of Units	Purchase Price
	 	 	 
	Ladenburg Thalmann Financial Services Inc.	50,000 (or 57,500 if the Over-Allotment Option is exercised in full)	$500,000 (or $575,00 if the Over-Allotment Option is exercised in full)
	B. Riley & Co., LLC	25,000 (or 28,750 if the Over-Allotment Option is exercised in full)	$250,000 (or $287,500 if the Over-Allotment Option is exercised in full) 
	FBR Capital Markets & Co.	25,000 (or 28,750 if the Over-Allotment Option is exercised in full)	$250,000 (or $287,500 if the Over-Allotment Option is exercised in full)


 


 


A-1