Exhibit 4.1


 


	NUMBER	UNITS
	U-	 



 


	SEE REVERSE FOR	Cactus Acquisition Corp. 1 Limited	 



 


 CERTAIN




 


 DEFINITIONS




 


	 	CUSIP  [●]



 


UNITS CONSISTING
OF ONE CLASS A ORDINARY SHARE AND ONE-HALF WARRANT,


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


 


	THIS CERTIFIES THAT	 	 



 


	is the owner of	 	  Units.



 


Each Unit
(“Unit”) consists of one (1) Class A ordinary share, par value $0.0001 per share (“Class A
ordinary shares”), of Cactus Acquisition Corp. 1 Limited , a Cayman Islands exempted company (the
“Company”), and one-half of one redeemable warrant (“Warrant”). Each Warrant
entitles the holder to purchase one (1) Class A ordinary share (subject to adjustment) for $11.50 per share (subject to adjustment).
Each Warrant will become exercisable thirty (30) days after the Company’s completion of a merger, amalgamation, 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 Class A ordinary shares and Warrants comprising the Units represented by this certificate will begin
separate trading on [●] unless Oppenheimer & Co. Inc. elects to allow earlier separate trading, 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 its initial public offering and issuing a press release
announcing when separate trading will begin. The terms of the Warrants are governed by a Warrant Agreement, dated as of [●],
2021, 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 One State Street, 30th Floor, New York, New York
10004, and are available to any Warrant holder on written request and without cost.


 


This certificate
is not valid unless countersigned by the Transfer Agent and 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 signatures of
its duly authorized officers.


 


	By 	        	 
	 	 	 
	 	Chief Executive Officer	 



 






     


     


    

 


Cactus Acquisition
Corp. 1 Limited 


 


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 shares 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 register of members 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.



 






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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 (OR ANY SUCCESSOR RULE) UNDER THE
SECURITIES EXCHANGE ACT OF 1934, AS AMENDED).


 






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In each case, as more fully described
in the Company’s final prospectus 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 its initial public offering only in the event that (i)
the Company redeems the Class A ordinary shares sold in its initial public offering and liquidates because it does not consummate an initial
business combination by a date calculated by reference to the Company’s amended and restated memorandum and articles of association,
(ii) the Company redeems the Class A ordinary shares sold in its initial public offering in connection with a shareholder vote to amend
the Company’s amended and restated memorandum and articles of association (a) to modify the substance or timing of the Company’s
obligation to redeem 100% of the Class A ordinary shares if it does not consummate an initial business combination by a date calculated
by reference to the Company’s amended and restated memorandum and articles of association or (b) with respect to any other provision
relating to shareholders’ rights or pre-initial business combination activity, or (iii) if the holder(s) seek(s) to redeem for cash
his, her or its respective Class A ordinary shares in connection with 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 initial business combination.
In no other circumstances shall the holder(s) have any right or interest of any kind in or to the trust account.


 


 


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