Exhibit
4.3


 


Form
of Warrant Certificate


 


[FACE]


 


Number


 


Warrants


 


THIS
WARRANT SHALL BE VOID IF NOT EXERCISED PRIOR TO


 


THE
EXPIRATION OF THE EXERCISE PERIOD PROVIDED FOR


 


IN
THE WARRANT AGREEMENT DESCRIBED BELOW


 


B.
RILEY PRINCIPAL MERGER CORP. II


 


Incorporated
Under the Laws of the State of Delaware


  


CUSIP
__________


 


Warrant
Certificate


 


This
Warrant Certificate certifies that              , or registered assigns, is the registered holder of warrant(s) evidenced hereby (the
“Warrants” and each, a “Warrant”) to purchase shares of Class A common stock,
$0.0001 par value per share (“Class A Common Stock”), of B. Riley Principal Merger Corp. II, a Delaware
corporation (the “Company”). Each whole Warrant entitles the holder, upon exercise during the Exercise
Period set forth in the Warrant Agreement referred to below, to receive from the Company that number of fully paid and non-assessable
shares of Class A Common Stock as set forth below, at the exercise price (the “Warrant Price”) as determined
pursuant to the Warrant Agreement, payable in lawful money (or through “cashless exercise” as provided
for in the Warrant Agreement) of the United States of America upon surrender of this Warrant Certificate and payment of the Warrant
Price at the office or agency of the Warrant Agent referred to below, subject to the conditions set forth herein and in the Warrant
Agreement. Defined terms used in this Warrant Certificate but not defined herein shall have the meanings given to them in the
Warrant Agreement.


 


Each
whole Warrant is initially exercisable for one fully paid and non-assessable share of Class A Common Stock. No fractional shares
will be issued upon exercise of any Warrant. If, upon the exercise of Warrants, a holder would be entitled to receive a fractional
interest in a share of Class A Common Stock, the Company will, upon exercise, round down to the nearest whole number the number
of shares of Class A Common Stock to be issued to the Warrant holder. The number of shares of Class A Common Stock issuable upon
exercise of the Warrants is subject to adjustment upon the occurrence of certain events as set forth in the Warrant Agreement.


 


The
initial Warrant Price per share of Class A Common Stock for any Warrant is equal to $11.50 per share. The Warrant Price is subject
to adjustment upon the occurrence of certain events set forth in the Warrant Agreement.


 


Subject
to the conditions set forth in the Warrant Agreement, the Warrants may be exercised only during the Exercise Period and to the
extent not exercised by the end of such Exercise Period, such Warrants shall become void.


 


Reference
is hereby made to the further provisions of this Warrant Certificate set forth on the reverse hereof and such further provisions
shall for all purposes have the same effect as though fully set forth at this place.


 


This
Warrant Certificate shall not be valid unless countersigned by the Warrant Agent, as such term is used in the Warrant Agreement.


 






     


     


    

 


This
Warrant Certificate shall be governed by and construed in accordance with the internal laws of the State of New York, without
regard to conflicts of laws principles thereof.


 


	 	B.
    RILEY PRINCIPAL MERGER CORP. II
	 	 	 
	 	By:	 
	 	Name:	 
	 	Title:  	 
	 	 	 
	 	CONTINENTAL
    STOCK TRANSFER & TRUST COMPANY, as Warrant Agent
	 	 	 
	 	By:	             
	 	Name:	 
	 	Title:  	 


 




     


     


    

 


[Form
of Warrant Certificate]


 


[Reverse]


 


The
Warrants evidenced by this Warrant Certificate are part of a duly authorized issue of Warrants entitling the holder on exercise
to receive shares of Class A Common Stock and are issued or to be issued pursuant to a Warrant Agreement dated as of                 , 2020 (the
“Warrant Agreement”), duly executed and delivered by the Company to Continental Stock Transfer &
Trust Company, a New York corporation, as warrant agent (the “Warrant Agent”), which Warrant Agreement
is hereby incorporated by reference in and made a part of this instrument and is hereby referred to for a description of the rights,
limitation of rights, obligations, duties and immunities thereunder of the Warrant Agent, the Company and the holders (the words
“holders” or “holder” meaning the Registered Holders or Registered Holder,
respectively) of the Warrants. A copy of the Warrant Agreement may be obtained by the holder hereof upon written request to the
Company. Defined terms used in this Warrant Certificate but not defined herein shall have the meanings given to them in the Warrant
Agreement.


 


Warrants
may be exercised at any time during the Exercise Period set forth in the Warrant Agreement. The holder of Warrants evidenced by
this Warrant Certificate may exercise them by surrendering this Warrant Certificate, with the form of election to purchase set
forth hereon properly completed and executed, together with payment of the Warrant Price as specified in the Warrant Agreement
(or through “cashless exercise” as provided for in the Warrant Agreement) at the principal corporate trust office
of the Warrant Agent. In the event that upon any exercise of Warrants evidenced hereby the number of Warrants exercised shall
be less than the total number of Warrants evidenced hereby, there shall be issued to the holder hereof or his, her or its assignee,
a new Warrant Certificate evidencing the number of Warrants not exercised.


 


Notwithstanding
anything else in this Warrant Certificate or the Warrant Agreement, no Warrant may be exercised unless at the time of exercise
(i) a registration statement covering the shares of Class A Common Stock to be issued upon exercise is effective under the Securities
Act and (ii) a prospectus thereunder relating to the shares of Class A Common Stock is current, except through “cashless
exercise” as provided for in the Warrant Agreement.


 


The
Warrant Agreement provides that upon the occurrence of certain events the number of shares of Class A Common Stock issuable upon
the exercise of the Warrants set forth on the face hereof may, subject to certain conditions, be adjusted. If, upon exercise of
a Warrant, the holder thereof would be entitled to receive a fractional interest in a share of Class A Common Stock, the Company
shall, upon exercise, round down to the nearest whole number of shares of Class A Common Stock to be issued to the holder of the
Warrant.


 


Warrant
Certificates, when surrendered at the principal corporate trust office of the Warrant Agent by the Registered Holder thereof in
person or by legal representative or attorney duly authorized in writing, may be exchanged, in the manner and subject to the limitations
provided in the Warrant Agreement, but without payment of any service charge, for another Warrant Certificate or Warrant Certificates
of like tenor evidencing in the aggregate a like number of Warrants.


 


Upon
due presentation for registration of transfer of this Warrant Certificate at the office of the Warrant Agent a new Warrant Certificate
or Warrant Certificates of like tenor and evidencing in the aggregate a like number of Warrants shall be issued to the transferee(s)
in exchange for this Warrant Certificate, subject to the limitations provided in the Warrant Agreement, without charge except
for any tax or other governmental charge imposed in connection therewith.


 


The
Company and the Warrant Agent may deem and treat the Registered Holder(s) hereof as the absolute owner(s) of this Warrant Certificate
(notwithstanding any notation of ownership or other writing hereon made by anyone), for the purpose of any exercise hereof, of
any distribution to the holder(s) hereof, and for all other purposes, and neither the Company nor the Warrant Agent shall be affected
by any notice to the contrary. Neither the Warrants nor this Warrant Certificate entitles any holder hereof to any rights of a
stockholder of the Company.



 






     


     


    

 


Election
to Purchase


 


(To
Be Executed Upon Exercise of Warrant)


 


The
undersigned hereby irrevocably elects to exercise the right, represented by this Warrant Certificate, to receive                 shares of Class
A Common Stock and herewith tenders payment for such shares of Class A Common Stock to the order of B. Riley Principal Merger
Corp. II (the “Company”) in the amount of $            in accordance with the terms hereof. The undersigned requests that
a certificate for such shares of Class A Common Stock be registered in the name of                 , whose address is                 and that such shares of
Class A Common Stock be delivered to whose address is                 . If said number of shares of Class A Common Stock is less than all of the
shares of Class A Common Stock purchasable hereunder, the undersigned requests that a new Warrant Certificate representing the
remaining balance of such shares of Class A Common Stock be registered in the name of                 , whose address is and that such Warrant
Certificate be delivered to                 , whose address is                 .


 


In
the event that the Warrant has been called for redemption by the Company pursuant to Section 6 of the Warrant Agreement
and the Company has required cashless exercise pursuant to Section 6.3 of the Warrant Agreement, the number of shares of
Class A Common Stock that this Warrant is exercisable for shall be determined in accordance with subsection 3.3.1(b) and
Section 6.3 of the Warrant Agreement.


 


In
the event that the Warrant is a Private Placement Warrant, a Working Capital Warrant or a Forward Purchase Warrant that is to
be exercised on a “cashless” basis pursuant to subsection 3.3.1(c) of the Warrant Agreement, the number of
shares of Class A Common Stock that this Warrant is exercisable for shall be determined in accordance with subsection 3.3.1(c)
of the Warrant Agreement.


 


In
the event that the Warrant is to be exercised on a “cashless” basis pursuant to Section 7.4 of the Warrant
Agreement, the number of shares of Class A Common Stock that this Warrant is exercisable for shall be determined in accordance
with Section 7.4 of the Warrant Agreement.


 


In
the event that the Warrant may be exercised, to the extent allowed by the Warrant Agreement, through cashless exercise (i) the
number of shares of Class A Common Stock that this Warrant is exercisable for would be determined in accordance with the relevant
section of the Warrant Agreement which allows for such cashless exercise and (ii) the holder hereof shall complete the following:
The undersigned hereby irrevocably elects to exercise the right, represented by this Warrant Certificate, through the cashless
exercise provisions of the Warrant Agreement, to receive shares of Class A Common Stock. If said number of shares of Class A Common
Stock is less than all of the shares of Class A Common Stock purchasable hereunder (after giving effect to the cashless exercise),
the undersigned requests that a new Warrant Certificate representing the remaining balance of such shares of Class A Common Stock
be registered in the name of                 , whose address is                 and that such Warrant Certificate be delivered to                 , whose address is                 .


 


[Signature
Page Follows]


 




     


     


    

 


	Date:                ,
    20    	 	 
	 	 	(Signature)
	 	 	 
	 	 	 
	 	 	 
	 	 	 
	 	 	(Address)
	 	 	 
	 	 	 
	 	 	(Tax
    Identification Number)
	Signature
    Guaranteed:	 	 
	 	 	 
	 	 	 


 


THE
SIGNATURE(S) SHOULD BE GUARANTEED BY AN ELIGIBLE GUARANTOR INSTITUTION (BANKS, STOCKBROKERS, SAVINGS AND LOAN ASSOCIATIONS AND
CREDIT UNIONS WITH MEMBERSHIP IN AN APPROVED SIGNATURE GUARANTEE MEDALLION PROGRAM, PURSUANT TO SEC RULE 17Ad-15 UNDER THE SECURITIES
EXCHANGE ACT OF 1934, AS AMENDED (OR ANY SUCCESSOR RULE).