Exhibit 10.6


 


THIS NOTE HAS NOT BEEN REGISTERED UNDER THE SECURITIES
ACT OF 1933, AS AMENDED (THE “SECURITIES ACT”). THIS NOTE HAS BEEN ACQUIRED FOR INVESTMENT ONLY AND MAY NOT BE SOLD, TRANSFERRED
OR ASSIGNED IN THE ABSENCE OF REGISTRATION OF THE RESALE THEREOF UNDER THE SECURITIES ACT OR AN OPINION OF COUNSEL REASONABLY SATISFACTORY
IN FORM, SCOPE AND SUBSTANCE TO THE COMPANY THAT SUCH REGISTRATION IS NOT REQUIRED.


PROMISSORY NOTE


	Principal Amount: $300,000	Dated as of                        , 2021


 


Aquarius
II Acquisition Corp., an exempted company in the Cayman Islands (the “Maker”), promises to pay to the order
of Aquarius II Sponsor Ltd. or its registered assigns or successors in interest (the “Payee”) the principal sum of
Three-Hundred Thousand Dollars ($300,000) in lawful money of the United States of America, on the terms and conditions described below.
All payments on this Note shall be made by check or wire transfer of immediately available funds or as otherwise determined by the Maker
to such account as the Payee may from time to time designate by written notice in accordance with the provisions of this Note.


 


		1.	Principal. The principal balance of this Promissory Note (this “Note”) shall
be payable promptly on the earlier of (i) December 31, 2021 and (ii) the date on which the Maker consummates an initial public offering
of its securities or the date on which the Company determines not to conduct an initial public offering of its securities. The principal
balance may be prepaid at any time.



 


		2.	Interest. No interest shall accrue on the unpaid principal balance of this Note.



 


		3.	Application of Payments. All payments shall be applied first to payment in full of any costs incurred
in the collection of any sum due under this Note, including (without limitation) reasonable attorney’s fees, then to the payment
in full of any late charges and finally to the reduction of the unpaid principal balance of this Note.



 


		4.	Events of Default. The following shall constitute an event of default (“Event of Default”):



 


		(a)	Failure to Make Required Payments. Failure by Maker to pay the principal of this Note within five
(5) business days following the date when due.



 


		(b)	Voluntary Liquidation, Etc. The commencement by Maker of a proceeding relating to its bankruptcy,
insolvency, reorganization, rehabilitation or other similar action, or the consent by it to the appointment of, or taking possession by,
a receiver, liquidator, assignee, trustee, custodian, sequestrator (or other similar official) for Maker or for any substantial part of
its property, or the making by it of any assignment for the benefit of creditors, or the failure of Maker generally to pay its debts as
such debts become due, or the taking of corporate action by Maker in furtherance of any of the foregoing.



 






     


     


    

 


		(c)	Involuntary Bankruptcy, Etc. The entry of a decree or order for relief by a court having jurisdiction
in the premises in respect of maker in an involuntary case under any applicable bankruptcy, insolvency or similar law, for the appointing
of a receiver, liquidator, assignee, custodian, trustee, sequestrator (or similar official) for Maker or for any substantial part of its
property, or ordering the winding-up or liquidation of the affairs of Maker, and the continuance of any such decree or order unstayed
and in effect for a period of 60 consecutive days.



 


		5.	Remedies.



 


		(a)	Upon the occurrence of an Event of Default specified in Section 4(a) hereof, Payee may, by written notice
to Maker, declare this Note to be due immediately and payable, whereupon the unpaid principal amount of this Note, and all other amounts
payable thereunder, shall become immediately due and payable without presentment, demand, protest or other notice of any kind, all of
which are hereby expressly waived, anything contained herein or in the documents evidencing the same to the contrary notwithstanding.



 


		(b)	Upon the occurrence of an Event of Default specified in Sections 4(b) and 4(c), the unpaid principal balance
of this Note, and all other sums payable with regard to this Note, shall automatically and immediately become due and payable, in all
cases without any action on the part of Payee.



 


		6.	Waivers. Maker and all endorsers and guarantors of, and sureties for, this Note waive presentment
for payment, demand, notice of dishonor, protest, and notice of protest with regard to the Note, all errors, defects and imperfections
in any proceedings instituted by Payee under the terms of this Note, and all benefits that might accrue to Maker by virtue of any present
or future laws exempting any property, real or personal, or any part of the proceeds arising from any sale of any such property, from
attachment, levy or sale under execution, or providing for any stay of execution, exemption from civil process, or extension of time for
payment; and Maker agrees that any real estate that may be levied upon pursuant to a judgment obtained by virtue hereof, on any writ of
execution issued hereon, may be sold upon any such writ in whole or in part in any order desired by Payee.



 


		7.	Unconditional Liability. Maker hereby waives all notices in connection with the delivery, acceptance,
performance, default, or enforcement of the payment of this Note, and agrees that its liability shall be unconditional, without regard
to the liability of any other party, and shall not be affected in any manner by any indulgence, extension of time, renewal, waiver or
modification granted or consented to by Payee, and consents to any and all extensions of time, renewals, waivers, or modifications that
may be granted by Payee with respect to the payment or other provisions of this Note, and agrees that additional makers, endorsers, guarantors,
or sureties may become parties hereto without notice to Maker or affecting Maker’s liability hereunder.



 






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		8.	Notices. Any notice called for hereunder shall be deemed properly given if (i) sent by certified
mail, return receipt requested, (ii) personally delivered, (iii) dispatched by any form of private or governmental express mail or delivery
service providing receipted delivery or (iv) sent by facsimile or (v) to the following addresses or to such other address as either party
may designate by notice in accordance with this Section:



 


If to Maker:


Aquarius II Sponsor Ltd.


Ritter House, Wickhams Cay II,


PO Box 3170,


Road Town, Tortola VG1110, British Virgin
Islands


 


If to Payee:


Aquarius II Acquisition Corp.


89 Nexus Way, Camana Bay,


Grand Cayman, KY1-9009, Cayman Islands


 


Notice shall be deemed given on the
earlier of (i) actual receipt by the receiving party, (ii) the date shown on a facsimile transmission confirmation, (iii) the date reflected
on a signed delivery receipt, or (iv) two (2) Business Days following tender of delivery or dispatch by express mail or delivery service.


 


		9.	Construction. THIS NOTE SHALL BE CONSTRUED AND ENFORCED IN ACCORDANCE WITH THE LAWS OF NEW YORK,
WITHOUT REGARD TO CONFLICT OF LAW PROVISIONS THEREOF.



 


		10.	Jurisdiction. The courts of New York have exclusive jurisdiction to settle any dispute arising
out of or in connection with this agreement (including a dispute relating to any non-contractual obligations arising out of or in connection
with this agreement) and the parties submit to the exclusive jurisdiction of the courts of New York.



 


		11.	Severability. Any provision contained in this Note which is prohibited or unenforceable in any
jurisdiction shall, as to such jurisdiction, be ineffective to the extent of such prohibition or unenforceability without invalidating
the remaining provisions hereof, and any such prohibition or unenforceability in any jurisdiction shall not invalidate or render unenforceable
such provision in any other jurisdiction.



 


		12.	Trust Waiver. Notwithstanding anything herein to the contrary, the Payee hereby waives any and
all right, title, interest or claim of any kind (“Claim”) in or to any amounts contained in the trust account in which
the proceeds of the initial public offering (the “IPO”) conducted by the Maker and the proceeds of the sale of securities
in a private placement to occur prior to the effectiveness of the IPO, as described in greater detail in the registration statement and
prospectus to be filed with the Securities and Exchange Commission in connection with the IPO, will be placed, and hereby agrees not to
seek recourse, reimbursement, payment or satisfaction for any Claim from the trust account or any distribution therefrom for any reason
whatsoever.



 






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		13.	Amendment; Waiver. Any amendment hereto or waiver of any provision hereof may be made with, and
only with, the written consent of the Maker and the Payee.



 


		14.	Assignment. No assignment or transfer of this Note or any rights or obligations hereunder may be
made by any party hereto (by operation of law or otherwise) without the prior written consent of the other party hereto and any attempted
assignment without the required consent shall be void.



 


		15.	Further Assurance. The Maker shall, at its own cost and expense, execute and do (or procure to
be executed and done by any other necessary party) all such deeds, documents, acts and things as the Payee may from time to time require
as may be necessary to give full effect to this Promissory Note.



 


IN WITNESS WHEREOF, Maker, intending to be legally
bound hereby, has caused this Note to be duly executed on the day and year first above written.


 


	 	Aquarius II Acquisition Corp.
	 	 	 
	 	By:	               
	 	Name:	Yan Zhang
	 	Title:	Director






 





	 	Agreed and acknowledged:
	 	 
	 	Aquarius II Sponsor Ltd.
	 	 	 
	 	By:	               
	 	Name:	Yan Zhang
	 	Title:	Director


 


 


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