Exhibit
4.2


 


	NUMBER	SHARES


 


______C


 


PETRA
ACQUISITION, INC.


 


INCORPORATED
UNDER THE LAWS OF DELAWARE


 


COMMON
STOCK


 


SEE
REVERSE FOR

CERTAIN DEFINITIONS


 


	This
    Certifies that	CUSIP
    716421 102
	 	 
	is
    the owner of	 


 


FULLY
PAID AND NON-ASSESSABLE SHARES OF COMMON STOCK OF THE PAR VALUE OF $0.001 EACH OF


 


PETRA
ACQUISITION, INC.


 


transferable
on the books of the Company in person or by duly authorized attorney upon surrender of this certificate properly endorsed.


The
Company will be forced to liquidate if it is unable to complete an initial business combination within the time period set forth
in the Company’s Certificate of Incorporation, as the same may be amended from time to time.

This certificate is not valid unless countersigned by the Transfer Agent and registered by the Registrar.

Witness the facsimile seal of the Company and the facsimile signatures of its duly authorized officers.


 


Dated:


 


	 	[Seal]	 
	CHAIRMAN	SECRETARY


  




    


     


    

  


The
following abbreviations, when used in the inscription on the face of this certificate, shall be construed as though they were
written out in full according to applicable laws or regulations:


 


	 	TEN
    COM –	as
    tenants in common	UNIF GIFT MIN ACT - _____ Custodian
______
	 	TEN
    ENT –	as
    tenants by the entireties	(Cust)               
    (Minor)
	 	JT
    TEN –	as
    joint tenants with right of survivorship	under
    Uniform Gifts to Minors
	 	 	and
    not as tenants in common	Act
    ______________
	 	 	 	(State)


 


Additional
abbreviations may also be used though not in the above list.


 


PETRA
ACQUISITION, INC.


 


The
Company will furnish without charge to each shareholder who so requests the powers, designations, preferences, and relative, participating,
optional, or other special rights of each class of stock or series thereof of the Company and the qualifications, limitations,
or restrictions of such preferences, and/or rights. This certificate and the shares represented thereby are issued and shall be
held subject to all the provisions of the Certificate of Incorporation and all amendments thereto and resolutions of the Board
of Directors (copies of which may be obtained from the secretary of the Company), to all of which the holder of this certificate
by acceptance hereof assents.


 


For
value received, ___________________________ hereby sell, assign and transfer unto


 


PLEASE
INSERT SOCIAL SECURITY OR OTHER


IDENTIFYING
NUMBER OF ASSIGNEE


 


	 

         
	 


  





(PLEASE
PRINT OR TYPEWRITE NAME AND ADDRESS, INCLUDING ZIP CODE, OF ASSIGNEE)


 


shares
of the capital stock represented by the within Certificate, and do hereby irrevocably constitute and appoint
_____________________________________________________________________________Attorney to transfer the said stock on the books
of the within named Company will full power of substitution in the premises.


 


	Dated	 	 	 	 
	 	 	 	 
	 	 	 	Notice:	The
    signature to this assignment must correspond with the name as written upon the face of the certificate in every particular,
    without alteration or enlargement or any change whatever.


 


Signature(s)
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 S.E.C. RULE 17Ad-15). 	 


 


The
holder(s) of this certificate shall be entitled to receive a pro-rata portion of the funds from the trust account only in the
event that (i) the Company is forced to liquidate because it does not consummate an initial business combination within the period
of time set forth in the Company’s Amended and Restated Certificate of Incorporation, as the same may be amended from time
to time (the “Charter”) or (ii) if the holder seeks to convert his shares upon consummation of, or sell his shares
in a tender offer in connection with, an initial business combination or in connection with certain amendments to the Charter.
In no other circumstances shall the holder(s) have any right or interest of any kind in or to the trust account.