Exhibit 4.1


 





SPECIMEN UNIT CERTIFICATE


 


NUMBER UNITS U-


 


	SEE REVERSE FOR 

CERTAIN

DEFINITIONS	Avista Public Acquisition Corp. II	 


 


CUSIP [ ]


 


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

REDEEMABLE


 


WARRANT 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 (“Ordinary Shares”), of Avista Public Acquisition Corp. II, a Cayman Islands exempted company
(the “Company”), and one-third (1/3) of one redeemable warrant (each whole warrant, a “Warrant”). Each Warrant
entitles the holder to purchase one (1) Ordinary Share for $11.50 per share (subject to adjustment). 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 or entities (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 Ordinary Shares and Warrants comprising the Units represented
by this certificate are not transferable separately prior to              , 2021, unless Credit Suisse Securities (USA) LLC elects to allow earlier
separate trading, subject to the Company’s filing with the Securities and Exchange Commission of a Current Report on Form 8-K containing
an audited balance sheet reflecting the Company’s receipt of the gross proceeds of the 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 are exerciseable. 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 the consummation of the Business Combination,
the Units represented by this certificate will automatically separate into the Class A Ordinary Shares and Warrants comprising such Units.


 


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	 	Chief  Financial Officer



 






     


     


    

 


Avista Public Acquisition Corp. II


 


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.


 



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For value received,                hereby sells, assigns and transfers 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

 OR ANY SUCCESSOR RULES).	 
	 	 	 


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 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 period of time set forth in the Company’s amended and restated memorandum and articles of association, as the same may
be amended from time to time, (ii) the Company redeems the 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) that would modify the substance or
timing of the Company’s obligation to provide holders of the Ordinary Shares the right to have their shares redeemed in connection
with the Company’s initial business combination or to redeem 100% of the Ordinary Shares if the Company does not complete its initial
business combination within the time period set forth therein or (B) with respect to any other provision relating to the rights of holders
of the Ordinary Shares, or (iii) if the holder(s) seek(s) to redeem for cash his, her or its respective 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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