Exhibit 4.1


 


	NUMBER	UNITS 


U-


 


SEE REVERSE FOR CERTAIN DEFINITIONS


 


CUSIP _______


 


TKB CRITICAL TECHNOLOGIES 1


 


UNITS CONSISTING OF ONE CLASS A ORDINARY SHARE
AND ONE-THIRD OF ONE

REDEEMABLE WARRANT, EACH WHOLE WARRANT ENTITLING THE HOLDER TO PURCHASE ONE CLASS A ORDINARY SHARE


 


THIS CERTIFIES THAT                     
is the owner of          Units of TKB Critical Technologies 1, a Cayman Islands exempted company
(the “Company”), transferable on the books of the Company in person or by duly authorized attorney upon surrender
of this certificate properly endorsed.


 


Each Unit (“Unit”)
consists of one Class A ordinary share, par value $0.0001 per share (“Ordinary Share”), of the Company
and one-third of one redeemable warrant (each whole warrant, a “Warrant”). Each whole Warrant entitles
the holder to purchase one Ordinary Share for $11.50 per share (subject to adjustment). Only whole Warrants are exercisable. Each
Warrant will become exercisable thirty (30) days after the Company’s completion of a merger, share exchange, asset acquisition,
share purchase, reorganization or other similar business combination with one or more businesses (each a “Business Combination”)
and will expire unless exercised before 5:00 p.m., New York City Time, on the date that is five (5) years after the date on which
the Company completes its initial Business Combination, or earlier upon redemption or liquidation (the “Expiration Date”). The
Ordinary Shares and Warrants comprising the Units represented by this certificate are not transferable separately prior to , 2021, unless
Jefferies LLC elects to allow separate trading earlier, subject to the Company’s filing of a Current Report on Form 8-K with
the Securities and Exchange Commission containing an audited balance sheet reflecting the Company’s receipt of the gross proceeds
of the Company’s initial public offering and issuing a press release announcing when separate trading will begin. No fractional
Warrants will be issued upon separation of the Units and only whole Warrants will trade. The terms of the Warrants are governed by a Warrant
Agreement, dated as of , 2021 (the “Warrant Agreement”), between the Company and Continental Stock Transfer &
Trust Company, as Warrant Agent, and are subject to the terms and provisions contained therein, all of which terms and provisions the
holder of this certificate consents to by acceptance hereof. Copies of the Warrant Agreement are on file at the office of the Warrant
Agent at 1 State Street, 30th Floor, New York, New York 10004, and are available to any Warrant holder on written request and
without cost.


 


Upon consummation of a Business Combination, the
Units represented by this certificate will automatically separate into the Ordinary Shares and Warrants comprising such Units.


 


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


 


This certificate shall be governed by and construed
in accordance with the internal laws of the State of New York.


 


Witness the facsimile signature of a duly authorized
signatory of the Company.


 


	 	 	 
	 	 	 
	Authorized Signatory	 	Transfer Agent




 



     


     


    

 


TKB CRITICAL TECHNOLOGIES 1


 


The Company will furnish without charge to each
unitholder who so requests, a statement of the powers, designations, preferences and relative, participating, optional or other special
rights of each class of equity or series thereof of the Company and the qualifications, limitations, or restrictions of such preferences
and/or rights.


 


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 and not as tenants in common	 	 	 	 	 	under Uniform Gifts to Minors Act
	 	 	 	 	 	 	
 



    (State)



 


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


 


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)


 


Units represented by the within certificate, and do hereby irrevocably
constitute and appoint 


 


Attorney to transfer the said Units on the books of the within
named Company with 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) MUST 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 UNDER THE SECURITIES EXCHANGE ACT OF 1934, AS AMENDED (OR ANY SUCCESSOR RULE)).	 


 


As more fully described
in, and subject to the terms and conditions described in, the Company’s final prospectus for its initial public offering dated                   ,
2021, the holder(s) of this certificate shall be entitled to receive a pro-rata portion of certain funds held in the trust account
established in connection with the Company’s initial public offering only in the event that (i) the Company redeems the Ordinary
Shares sold in its initial public offering and liquidates because it does not consummate an initial Business Combination within the time
period set forth in the Company’s Amended and Restated Memorandum and Articles of Association, as the same may be amended from time
to time, or (ii) if the holder(s) properly redeem for cash his, her or its respective Ordinary Shares included in the Units represented
by this certificate in connection with (x) a tender offer (or proxy solicitation, solely in the event the Company seeks shareholder approval
of the proposed initial Business Combination ) setting forth the details of a proposed Business Combination or (y) a shareholder vote
to amend the Company’s Amended and Restated Memorandum and Articles of Association, as the same may be amended from time to time,
(A) to modify the substance or timing of the Company’s obligation to allow redemption in connection with our initial Business Combination
or to redeem 100% of the Ordinary Shares if it does not consummate an initial Business Combination within the time period set forth in
the Company’s Amended and Restated Memorandum and Articles of Association or (B) with respect to any other material provisions relating
to shareholders’ rights or pre-initial Business Combination activity. In no other circumstances shall the holder(s) have any
right or interest of any kind in or to the trust account.