Exhibit 10.2


 


INVESTMENT MANAGEMENT TRUST AGREEMENT


 


This Investment Management
Trust Agreement (this “Agreement”) is made effective as of [●], 2021, by and between Mount Rainier Acquisition
Corp., a Delaware corporation (the “Company”), and American Stock Transfer & Trust Company, LLC , a New
York limited liability trust company (the “Trustee”).


 


WHEREAS, the Company’s
registration statement on Form S-1, File No. 333-256816 (the “Registration Statement”) and prospectus
(the “Prospectus”) for the initial public offering of the Company’s units (the “Units”),
each of which consists of one share of the Company’s common stock, par value $0.0001 per share (the “Common Stock”),
and one redeemable warrant to purchase three-fourths (3/4) of a share of Common Stock at a price of $11.50 per whole share, , subject
to adjustment (such initial public offering hereinafter referred to as the “Offering”), has been declared effective
as of the date hereof by the U.S. Securities and Exchange Commission;


 


WHEREAS, the Company has entered
into an Underwriting Agreement, dated [●], 2021 (the “Underwriting Agreement”), with A.G.P./Alliance Global
Partners, as representative (the “Representative”) of the several underwriters named therein (the “Underwriters”);


 


WHEREAS, as described in the
Prospectus, $150,000,000 of the gross proceeds of the Offering and sale of the Private Units (as defined in the Underwriting
Agreement) (or $172,500,000, if the Underwriters’ over-allotment option is exercised in full) will be delivered to the Trustee to
be deposited and held in a segregated trust account located at all times in the United States (the “Trust Account”)
for the benefit of the Company, the holders of the Common Stock included in the Units issued in the Offering and the Underwriters as hereinafter
provided (the amount to be delivered to the Trustee (and any interest subsequently earned thereon) is referred to herein as the “Property,”
the stockholders for whose benefit the Trustee shall hold the Property will be referred to as the “Public Stockholders,”
and the Public Stockholders, the Company and the Underwriters will be referred to together as the “Beneficiaries”);


 


WHEREAS, pursuant to the Underwriting
Agreement, a portion of the Property equal to $6,000,000, or $6,900,000 if the Underwriters’ over-allotment option is exercised
in full, is attributable to a business combination fee that will be payable by the Company to the Representative upon and concurrently
with the consummation of the Business Combination (as defined below) (the “Business Combination Fee”); and


 


WHEREAS, the Company and the
Trustee desire to enter into this Agreement to set forth the terms and conditions pursuant to which the Trustee shall hold the Property.


 


NOW THEREFORE, IT IS AGREED:


 


1.             
Agreements and Covenants of Trustee. The Trustee hereby agrees and covenants to:


 






     


     


    

 


(a)          Hold
the Property in trust for the Beneficiaries in accordance with the terms of this Agreement in the Trust Account, which Trust Account
shall be established by the Trustee in the United States at [●] and at a brokerage institution selected by the Trustee that is
reasonably satisfactory to the Company;


 


(b)         
Manage, supervise and administer the Trust Account subject to the terms and conditions set forth herein;


 


(c)         
In a timely manner, upon the written instruction of the Company, invest and reinvest the Property solely in United States
government securities within the meaning of Section 2(a)(16) of the Investment Company Act of 1940, as amended (the “Investment
Company Act”), having a maturity of 180 days or less, or in money market funds meeting the conditions of paragraphs (d)(1),
(d)(2), (d)(3) and (d)(4) of Rule 2a-7 promulgated under the Investment Company Act (or any successor rule), which invest only in direct
U.S. government treasury obligations, as determined by the Company, it being understood that the Trustee has no obligation to monitor
or question the Company’s determination that an investment is in compliance with the foregoing clause; Company shall not instruct
the Trustee to invest in any other securities or assets; it being understood that the Trust Account will earn no interest while account
funds are uninvested awaiting the Company’s instructions hereunder and the Trustee may earn bank credits or other consideration
during such periods;


 


(d)        
Collect and receive, when due, all interest or other income arising from the Property, which shall become part of the “Property,”
as such term is used herein;


 


(e)         
Promptly notify the Company and the Representative of all communications received by the Trustee with respect to any Property
requiring action by the Company;


 


(f)          
Supply any necessary information or documents as may be requested by the Company (or its authorized agents) in connection
with the Company’s preparation of the tax returns relating to assets held in the Trust Account;


 


(g)        
Participate in any plan or proceeding for protecting or enforcing any right or interest arising from the Property if, as
and when instructed by the Company to do so;


 


(h)         
Render to the Company, and to such other person as the Company may instruct, monthly written statements of the activities
of, and amounts in, the Trust Account reflecting all receipts and disbursements of the Trust Account;


 






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(i)           Commence
liquidation of the Trust Account only after and promptly after (x) receipt of, and only in accordance with, the terms of a
letter from the Company (“Termination Letter”) in a form substantially similar to that attached hereto as
either Exhibit A or Exhibit B, as applicable, signed on behalf of the Company by its Chief Executive
Officer, Chief Financial Officer, President, Vice President, Secretary or Chairman of the board of directors of the Company (the
 “Board”) or other authorized officer of the Company, and complete the liquidation of the Trust Account and
distribute the Property in the Trust Account, including interest not previously released to the Company to pay its taxes (less up to
$100,000 of interest that may be released to the Company to pay dissolution expenses in the case of a Termination Letter in the form
of Exhibit B hereto), only as directed in the Termination Letter and the other documents referred to therein, or (y) upon the date
which is, the later of (1) 15 months after the closing of the Offering and (2) such later date as may be approved by the
Company’s stockholders in accordance with the Company’s amended and restated certificate of incorporation (the
 “Amended and Restated Certificate of Incorporation”) if a Termination Letter has not been received by the
Trustee prior to such date, in which case the Trust Account shall be liquidated in accordance with the procedures set forth in the
form of letter attached hereto as Exhibit B and the Property in the Trust Account, including interest not previously
released to the Company to pay its taxes (less up to $100,000 of interest that may be released to the Company to pay dissolution
expenses) shall be distributed to the Public Stockholders of record as of such date; provided, however, that in the
event the Trustee receives a Termination Letter in a form substantially similar to Exhibit B hereto, or if the Trustee
begins to liquidate the Property because it has received no such Termination Letter by the date specified in clause (y) of this
Section 1(i), the Trustee shall keep the Trust Account open until twelve (12) months following the date the Property has been
distributed to the Public Stockholders;


 


(j)          
Upon written request from the Company, which may be given from time to time in a form substantially similar to that attached
hereto as Exhibit C, withdraw from the Trust Account and distribute to the Company the amount of interest earned on the Property
requested by the Company to cover any tax obligation owed by the Company as a result of assets of the Company or interest or other income
earned on the Property, which amount shall be delivered directly to the Company by electronic funds transfer or other method of prompt
payment, and the Company shall forward such payment to the relevant taxing authority; provided, however, that to the extent
there is not sufficient cash in the Trust Account to pay such tax obligation, the Trustee shall liquidate such assets held in the Trust
Account as shall be designated by the Company in writing to make such distribution, so long as such distribution shall not result in a
reduction in the principal amount initially deposited in the Trust Account; provided, further, that if the tax to be paid
is a franchise tax, the written request by the Company to make such distribution shall be accompanied by a copy of the franchise tax bill
from the State of Delaware for the Company (it being acknowledged and agreed that any such amount in excess of interest income earned
on the Property shall not be payable from the Trust Account). The written request of the Company referenced above shall constitute presumptive
evidence that the Company is entitled to said funds, and the Trustee shall have no responsibility to look beyond said request;


 


(k)         
Upon written request from the Company, which may be given from time to time in a form substantially similar to that attached
hereto as Exhibit D, distribute on behalf of the Company the amount requested by the Company to be used to redeem shares of Common
Stock from Public Stockholders properly submitted for redemption in connection with a stockholder vote to approve (i) an amendment to
the Amended and Restated Certificate of Incorporation to modify the substance or timing of the ability of Public Stockholders to seek
redemption in connection with an initial Business Combination or the Company’s obligation to redeem 100% of its public shares of
Common Stock if the Company has not consummated an initial Business Combination within such time as is described in the Amended and Restated
Certificate of Incorporation or (ii) an amendment with respect to any other provision of the Amended and Restated Certificate of Incorporation
relating to stockholders’ rights or pre-initial Business Combination activity. The written request of the Company referenced above
shall constitute presumptive evidence that the Company is entitled to distribute said funds, and the Trustee shall have no responsibility
to look beyond said request; and


 


(l)          
Not make any withdrawals or distributions from the Trust Account other than pursuant to Section 1(i), (j),
(k) or (l) above.


 






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2.             
Agreements and Covenants of the Company. The Company hereby agrees and covenants to:


 


(a)         
Give all instructions to the Trustee hereunder in writing, signed by the Company’s Chairman of the Board, Chief Executive
Officer, Chief Financial Officer, President, Executive Vice President, Vice President or Secretary. In addition, except with respect to
its duties under Sections 1(i), 1(j), 1(k) and 1(l) hereof, the Trustee shall be entitled to rely on, and shall be
protected in relying on, any verbal or telephonic advice or instruction which it, in good faith and with reasonable care, believes to
be given by any one of the persons authorized above to give written instructions, provided that the Company shall promptly confirm such
instructions in writing;


 


(b)         Subject
to Section 4 hereof, hold the Trustee harmless and indemnify the Trustee from and against any and all expenses,
including reasonable counsel fees and disbursements, or losses suffered by the Trustee in connection with any action taken by it
hereunder and in connection with any action, suit or other proceeding brought against the Trustee involving any claim, or in
connection with any claim or demand, which in any way arises out of or relates to this Agreement, the services of the Trustee
hereunder, or the Property or any interest earned on the Property, except for expenses and losses resulting from the Trustee’s
gross negligence, fraud or willful misconduct (as determined by a court of competent jurisdiction in a final and non-appealable decision). Promptly after the receipt by the Trustee of notice of demand or claim or the
commencement of any action, suit or proceeding, pursuant to which the Trustee intends to seek indemnification under this Section 2(b),
it shall notify the Company in writing of such claim (hereinafter referred to as the “Indemnified Claim”).
The Trustee shall have the right to conduct and manage the defense against such Indemnified Claim; provided that the Trustee
shall obtain the consent of the Company with respect to the selection of counsel, which consent shall not be unreasonably withheld.
The Trustee may not agree to settle any Indemnified Claim without the prior written consent of the Company, which such consent shall
not be unreasonably withheld. The Company may participate in such action with its own counsel;


 


(c)          Pay
the Trustee the fees set forth on Schedule A hereto, including an initial acceptance fee, annual administration fee, and
transaction processing fee which fees shall be subject to modification by the parties from time to time. It is expressly understood that
the Property shall not be used to pay such fees unless and until the closing of the Business Combination. The Company shall pay the Trustee
the initial acceptance fee and the first annual administration fee at the consummation of the Offering. The Trustee shall refund to the
Company the annual administration fee (on a pro rata basis) with respect to any period after the liquidation of the Trust Account. The
Company shall not be responsible for any other fees or charges of the Trustee except as set forth in this Section 2(c), Schedule
A and as may be provided in Section 2(b) hereof;


 


(d)        
In connection with any vote of the Company’s stockholders regarding a merger, capital stock exchange, asset acquisition,
stock purchase, reorganization or similar business combination involving the Company and one or more businesses (a “Business
Combination”), provide to the Trustee an affidavit or certificate of the inspector of elections for the stockholder meeting
verifying the vote of such stockholders regarding such Business Combination;


 






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(e)         
Provide the Representative with a copy of any Termination Letter(s) and/or any other correspondence that is sent to the
Trustee with respect to any proposed withdrawal from the Trust Account promptly after it issues the same;


 


(f)         
Unless otherwise agreed between the Company and the Representative, ensure that any Instruction Letter (as defined in Exhibit
A) delivered in connection with a Termination Letter in the form of Exhibit A expressly provides that the Business Combination Fee is
paid directly to the account or accounts directed by the Representative prior to any transfer of the funds held in the Trust Account to
the Company or any other person;


 


(g)          Instruct
the Trustee to make only those distributions that are permitted under this Agreement, and refrain from instructing the Trustee to make
any distributions that are not permitted under this Agreement; and


 


(h)          Within
four (4) business days after the Underwriters exercise their over-allotment option in connection with the Offering (or any unexercised
portion thereof) or such over-allotment expires, provide the Trustee with a notice in writing of the total amount of the Business Combination
Fee, which shall in no event be less than $6,000,000.


 


3.             
Limitations of Liability. The Trustee shall have no responsibility or liability to:


 


(a)         
Imply obligations, perform duties, inquire or otherwise be subject to the provisions of any agreement or document other
than this Agreement and that which is expressly set forth herein;


 


(b)         
Take any action with respect to the Property, other than as directed in Section 1 hereof, and the Trustee shall
have no liability to any third party except for liability arising out of the Trustee’s gross negligence, fraud or willful misconduct,
and in no event shall the Trustee be liable for the selection of investments or for investment losses incurred thereon or for losses incurred
as a result of the liquidation of any such investment prior to its maturity date or the failure of the Company to provide timely written
investment instruction;


 


(c)         
Institute any proceeding for the collection of any principal and income arising from, or institute, appear in or defend
any proceeding of any kind with respect to, any of the Property unless and until it shall have received instructions from the Company
given as provided herein to do so and the Company shall have advanced or guaranteed to it funds sufficient to pay any expenses incident
thereto;


 


(d)         
Refund any depreciation in principal of any Property;


 


(e)        
Assume that the authority of any person designated by the Company to give instructions hereunder shall not be continuing
unless provided otherwise in such designation, or unless the Company shall have delivered a written revocation of such authority to the
Trustee;


 






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(f)          The
other parties hereto or to anyone else for any action taken or omitted by it, or any action suffered by it to be taken or omitted,
in good faith and in the Trustee’s best judgment, except for the Trustee’s gross negligence, fraud or willful
misconduct. The Trustee may rely conclusively and shall be protected in acting upon any order, notice, demand, certificate, opinion
or advice of counsel (including counsel chosen by the Trustee, which counsel may be the Company’s counsel), statement,
instrument, report or other paper or document (not only as to its due execution and the validity and effectiveness of its
provisions, but also as to the truth and acceptability of any information therein contained) which the Trustee believes, in good
faith and with reasonable care, to be genuine and to be signed or presented by the proper person or persons. The Trustee shall not
be bound by any notice or demand, or any waiver, modification, termination or rescission of this Agreement or any of the terms
hereof, unless evidenced by a written instrument delivered to the Trustee, signed by the proper party or parties and, if the duties
or rights of the Trustee are affected, unless it shall give its prior written consent thereto;


 


(g)        
Verify the accuracy of the information contained in the Registration Statement;


 


(h)         
Provide any assurance that any Business Combination entered into by the Company or any other action taken by the Company
is as contemplated by the Registration Statement;


 


(i)          
File information returns with respect to the Trust Account with any local, state or federal taxing authority or provide
periodic written statements to the Company documenting the taxes payable by the Company, if any, relating to any interest income earned
on the Property;


 


(j)          
Prepare, execute and file tax reports, income or other tax returns and pay any taxes with respect to any income generated
by, and activities relating to, the Trust Account, regardless of whether such tax is payable by the Trust Account or the Company, including,
but not limited to, franchise and income tax obligations, except pursuant to Section 1(j) hereof; or


 


(k)         
Verify calculations, qualify or otherwise approve the Company’s written requests for distributions pursuant to Sections 1(i),
1(j), 1(k) or 1(l) hereof.


 


4.             
Trust Account Waiver. The Trustee has no right of set-off or any right, title, interest or claim of any kind (“Claim”)
to, or to any monies in, the Trust Account, and hereby irrevocably waives any Claim to, or to any monies in, the Trust Account that it
may have now or in the future. In the event the Trustee has any Claim against the Company under this Agreement, including, without limitation,
under Section 2(b) or Section 2(c) hereof, the Trustee shall pursue such Claim solely against the Company and
its assets outside the Trust Account and not against the Property or any monies in the Trust Account.


 


5.             
Termination. This Agreement shall terminate as follows:


 


(a)          If
the Trustee gives written notice to the Company that it desires to resign under this Agreement, the Company shall use its reasonable
efforts to locate a successor trustee, pending which the Trustee shall continue to act in accordance with this Agreement. At such
time that the Company notifies the Trustee that a successor trustee has been appointed and has agreed to become subject to the terms
of this Agreement, the Trustee shall transfer the management of the Trust Account to the successor trustee, including but not
limited to the transfer of copies of the reports and statements relating to the Trust Account, whereupon this Agreement shall
terminate; provided, however, that in the event that the Company does not locate a successor trustee within ninety
(90) days of receipt of the resignation notice from the Trustee, the Trustee may submit an application to have the Property
deposited with any court in the State of New York or with the United States District Court for the Southern District of New York and
upon such deposit, the Trustee shall be immune from any liability whatsoever; or


 






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(b)        
At such time that the Trustee has completed the liquidation of the Trust Account and its obligations in accordance with
the provisions of Section 1(i) hereof and distributed the Property in accordance with the provisions of the Termination Letter,
this Agreement shall terminate except with respect to Section 2(b).


 


6.             
Miscellaneous.


 


(a)         
The Company and the Trustee each acknowledge that the Trustee will follow the security procedures set forth below with respect
to funds transferred from the Trust Account. The Company and the Trustee will each restrict access to confidential information relating
to such security procedures to authorized persons. Each party must notify the other party immediately if it has reason to believe unauthorized
persons may have obtained access to such confidential information, or of any change in its authorized personnel. In executing funds transfers,
the Trustee shall rely upon all information supplied to it by the Company, including, account names, account numbers, and all other identifying
information relating to a Beneficiary, Beneficiary’s bank or intermediary bank. Except for any liability arising out of the Trustee’s
gross negligence, fraud or willful misconduct, the Trustee shall not be liable for any loss, liability or expense resulting from any error
in the information or transmission of the funds.


 


(b)        
This Agreement shall be governed by and construed and enforced in accordance with the laws of the State of New York, without
giving effect to conflicts of law principles that would result in the application of the substantive laws of another jurisdiction. This
Agreement may be executed in several original or facsimile counterparts, each one of which shall constitute an original, and together
shall constitute but one instrument.


 


(c)        
This Agreement contains the entire agreement and understanding of the parties hereto with respect to the subject matter
hereof. Subject to section 6(d), this Agreement or any provision hereof may only be changed, amended or modified (other than to correct
a typographical error) by a writing signed by each of the parties hereto.


 


(d)         This
Agreement or any provision hereof may only be changed, amended or modified pursuant to Section 6(c) hereof with the
Consent of the Stockholders. For purposes of this Section 6(d), the “Consent of the
Stockholders” means receipt by the Trustee of a certificate from the inspector of elections of the stockholder meeting
certifying that the Company’s stockholders of record as of a record date established in accordance with Section 213(a) of
the Delaware General Corporation Law, as amended (“DGCL”) (or any successor rule), who hold sixty-five
percent (65%) or more of all then outstanding shares of the Common Stock, of the Company voting together as a single class, have
voted in favor of such change, amendment or modification. No such amendment will affect any Public Stockholder who has otherwise
properly indicated his election to redeem his shares of Common Stock in connection with such stockholder vote. Except for any
liability arising out of the Trustee’s gross negligence, fraud or willful misconduct, the Trustee may rely conclusively on the
certification from the inspector or elections referenced above and shall be relieved of all liability to any party for executing the
proposed amendment in reliance thereon.


 






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(e)         
The parties hereto consent to the jurisdiction and venue of any state or federal court located in the City of New York,
State of New York, for purposes of resolving any disputes hereunder. AS TO ANY CLAIM, CROSS-CLAIM OR COUNTERCLAIM IN ANY WAY RELATING
TO THIS AGREEMENT, EACH PARTY WAIVES THE RIGHT TO TRIAL BY JURY.


 


(f)         
Any notice, consent or request to be given in connection with any of the terms or provisions of this Agreement shall be
in writing and shall be sent by express mail or similar private courier service, by certified mail (return receipt requested), by hand
delivery or by electronic mail:


 


if to the Trustee, to:


 


American Stock Transfer & Trust Company, LLC


6201 15th Avenue |


Brooklyn, NY 11219


Attn: Relationship Management


Email: 


 


if to the Company, to:


 


Mount Rainier Acquisition Corp.


256 W. 38th Street, 15th Floor


New York, NY 10018


Attn: Matthew Kearney, Chief Executive Officer


 


in each case, with copies to:


 


Loeb & Loeb LLP


345 Park Avenue


New York, New York 10154


Attn: Mitchell Nussbaum, Esq.


Email: 


and


A.G.P./Alliance Global Partners


590 Madison Avenue,
28th Floor 


New York, NY 10022 


Email: 


and


Manatt, Phelps & Phillips LLP


695 Town Center Drive, 14th Floor


Costa Mesa, California 92626


Attn: Thomas J. Poletti , Esq.


Email: 


 






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(g)         
Each of the Company and the Trustee hereby represents that it has the full right and power and has been duly authorized
to enter into this Agreement and to perform its respective obligations as contemplated hereunder. The Trustee acknowledges and agrees
that it shall not make any claims or proceed against the Trust Account, including by way of set-off, and shall not be entitled to any
funds in the Trust Account under any circumstance.


 


(h)        
This Agreement is the joint product of the Trustee and the Company and each provision hereof has been subject to the mutual
consultation, negotiation and agreement of such parties and shall not be construed for or against any party hereto.


 


(i)         
This Agreement may be executed in any number of counterparts, each of which shall be deemed to be an original, but all such
counterparts shall together constitute one and the same instrument. Delivery of a signed counterpart of this Agreement by facsimile or
electronic transmission shall constitute valid and sufficient delivery thereof.


 


(j)          
Each of the Company and the Trustee hereby acknowledges and agrees that the Underwriters are a third party beneficiaries
of this Agreement.


 


(k)         
Except as specified herein, no party to this Agreement may assign its rights or delegate its obligations hereunder to any
other person or entity.


[Signature Page Follows]


 






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IN WITNESS WHEREOF,
the parties have duly executed this Investment Management Trust Agreement as of the date first written above.


 


	 	AMERICAN STOCK TRANSFER & TRUST COMPANY, LLC , as Trustee
	 	 
	 	By  	 
	 	 	Name:
	 	 	Title:
	 	 
	 	MOUNT RAINIER ACQUISITION CORP.
	 	 
	 	By  	 
	 	 	Name: Matthew Kearney
	 	 	Title: Chief Executive Officer




 


[Signature Page to Investment Management Trust
Agreement]


 






     
 


     


    

 


SCHEDULE A


 


 


	Fee Item	Time and method of payment	Amount
	Initial set-up fee.	Initial closing of Offering by wire transfer.	$	$
	Trustee administration fee	Payable annually. First year fee payable, at initial closing of Offering by wire transfer, thereafter by wire transfer or check.	$	$
	Transaction processing fee for disbursements to Company under Sections 1(i), (j), (k) and (l)	Deduction by Trustee from accumulated income following disbursement made to Company under Section 1	$	$
	Paying Agent services as required pursuant to Section 1(i), (j), (k) and (l)	Billed to Company upon delivery of service pursuant to Section 1(i), (j), (k) and (l)	 	Prevailing rates



 






     
 


     


    

 


EXHIBIT A


 


[Letterhead of Company]


 


[Insert date]


 


American Stock Transfer & Trust Company, LLC


6201 15th Avenue |


Brooklyn, NY 11219


Attn: Relationship Management


 


Re:        Trust Account No.               
Termination Letter


 


Ladies and Gentlemen:


 


Pursuant to Section 1(i) of
the Investment Management Trust Agreement between Mount Rainier Acquisition Corp. (the “Company”) and American
Stock Transfer & Trust Company, LLC (the “Trustee”), dated as of [●], 2021 (the “Trust
Agreement”), this is to advise you that the Company has entered into an agreement with ___________________ (the “Target
Business”) to consummate a business combination with Target Business (the “Business Combination”)
on or about [insert date]. The Company shall notify you at least forty-eight (48) hours (or such shorter time as you may agree) in advance
of the actual date fixed for the consummation of the Business Combination (the “Consummation Date”). Capitalized
terms used but not defined herein shall have the meanings set forth in the Trust Agreement.


 


In accordance with the terms
of the Trust Agreement, we hereby authorize you to commence to liquidate all of the assets of the Trust Account on [insert date], such
that, on the Consummation Date, all of the funds held in the Trust Account will be immediately available for transfer to the account or
accounts that the Company shall direct on the Consummation Date (including as directed to it by the Representative (with respect to the
Business Combination Fee)). It is acknowledged and agreed that while the funds are on deposit in the Trust Account awaiting distribution,
the Company will not earn any interest or dividends.


 


On the Consummation Date
(i) counsel for the Company shall deliver to you written notification that the Business Combination has been consummated, or will be
consummated substantially concurrently with your transfer of funds to the accounts as directed by the Company (the
 “Notification”) and (ii) the Company shall deliver to you (a) a certificate of its Chief Executive Officer
(the “Vote Verification Certificate”), which verifies either that (i) the Business Combination has been
approved by a vote of the Company’s stockholders, if a vote is held or (ii) no vote of the Company’s stockholders for
the approval of the Business Combination is required and none has been held, and (b) a joint written instruction signed by the
Company and the Representative with respect to the transfer of the funds held in the Trust Account, including payment of amounts
owed to Public Stockholders who have properly exercised their redemption rights and payment of the Business Combination Fee to the
Representative from the Trust Account (the “Instruction Letter”). You are hereby directed and authorized
to transfer the funds held in the Trust Account immediately upon your receipt of the Notification, the Vote Verification Certificate
and the Instruction Letter, in accordance with the terms of the Instruction Letter. In the event that certain deposits held in the
Trust Account may not be liquidated by the Consummation Date without penalty, you will notify the Company in writing of the same and
the Company shall direct you as to whether such funds should remain in the Trust Account and be distributed after the Consummation
Date to the Company. Upon the distribution of all the funds, net of any payments necessary for reasonable unreimbursed expenses
related to liquidating the Trust Account, your obligations under the Trust Agreement shall be terminated.


 






     
 


     


    

 


In the event that the Business
Combination is not consummated on the Consummation Date described in the notice thereof and we have not notified you on or before the
original Consummation Date of a new Consummation Date, then upon receipt by you of written instructions from the Company, the funds held
in the Trust Account shall be reinvested as provided in Section 1(c) of the Trust Agreement on the business day immediately following
such original Consummation Date as set forth in such notice or as soon thereafter as possible.


 


	 	Very truly yours,
	 	 
	 	Mount Rainier Acquisition Corp.
	 	 
	 	By  	 
	 	 	Name:
	 	 	Title:




 


cc:        A.G.P./Alliance Global Partners


 






     
 


     


    

 


EXHIBIT B


 


[Letterhead of Company]


 


[Insert date]


 


American Stock Transfer & Trust Company, LLC


6201 15th Avenue |


Brooklyn, NY 11219


Attn: Relationship Management


 


Re:      Trust Account No.                   
Termination Letter


 


Ladies and Gentlemen:


 


Pursuant to Section 1(i)
of the Investment Management Trust Agreement between Mount Rainier Acquisition Corp. (the “Company”) and American
Stock Transfer & Trust Company, LLC (the “Trustee”), dated as of [●], 2021 (the “Trust
Agreement”), this is to advise you that the Company has been unable to effect a Business Combination within the time frame
specified in the Company’s Amended and Restated Certificate of Incorporation, as described in the Company’s Prospectus relating
to the Offering. Capitalized terms used but not defined herein shall have the meanings set forth in the Trust Agreement.


 


In accordance with the terms
of the Trust Agreement, we hereby authorize you to liquidate all of the assets in the Trust Account on ____________, 20__ and keep the
total proceeds thereof in the Trust Account to await distribution to the Public Stockholders. The Company has selected _______________
1 as the effective date for the purpose
of determining when the Public Stockholders will be entitled to receive their share of the liquidation proceeds. You agree to be the Paying
Agent of record and, in your separate capacity as Paying Agent, agree to distribute said funds directly to the Public Stockholders in
accordance with the terms of the Trust Agreement and the Amended and Restated Certificate of Incorporation of the Company. Upon the distribution
of all the funds, net of any payments necessary for reasonable unreimbursed expenses related to liquidating the Trust Account, your obligations
under the Trust Agreement shall be terminated, except to the extent otherwise provided in Section 1(i) of the Trust Agreement.


 


	 	Very truly yours,
	 	 
	 	Mount Rainier Acquisition Corp.
	 	 
	 	By  	 
	 	 	Name:
	 	 	Title:




 


cc:       A.G.P./Alliance Global Partners


 


 






1 15 months from the closing of the Offering.


 






     
 


     


    

 


EXHIBIT C


 


[Letterhead of Company]


 


[Insert date]


 


American Stock Transfer & Trust Company, LLC


6201 15th Avenue |


Brooklyn, NY 11219


Attn: Relationship Management


 


Re:       Trust Account No.
                        Tax
Withdrawal Instruction


 


Ladies and Gentlemen:


 


Pursuant to Section 1(j)
of the Investment Management Trust Agreement between Mount Rainier Acquisition Corp. (the “Company”) and American
Stock Transfer & Trust Company, LLC (the “Trustee”), dated as of [●], 2021 (the “Trust
Agreement”), the Company hereby requests that you deliver to the Company $______________ of the interest income earned on
the Property as of the date hereof. Capitalized terms used but not defined herein shall have the meanings set forth in the Trust Agreement.


 


The Company needs such funds
to pay for the tax obligations as set forth on the attached tax return or tax statement. In accordance with the terms of the Trust Agreement,
you are hereby directed and authorized to transfer (via wire transfer) such funds promptly upon your receipt of this letter to the Company’s
operating account at:


[WIRE INSTRUCTION INFORMATION]


 


	 	Very truly yours,
	 	 
	 	Mount Rainier Acquisition Corp.
	 	 
	 	By  	 
	 	 	Name:
	 	 	Title:




 


cc:       A.G.P./Alliance Global Partners


 






     
 


     


    

 


EXHIBIT D


 


[Letterhead of Company]


 


[Insert date]


 


American Stock Transfer & Trust Company, LLC


6201 15th Avenue |


Brooklyn, NY 11219


Attn: Relationship Management


 


Re:       Trust Account No.                 Stockholder
Redemption Withdrawal Instruction


 


Gentlemen:


 


Pursuant to Section
1(k) of the Investment Management Trust Agreement between Mount Rainier Acquisition Corp. (the “Company”)
and American Stock Transfer & Trust Company, LLC (the “Trustee”), dated as of [●], 2021 (the “Trust
Agreement”), the Company hereby requests that you deliver $_____________ of the principal and interest income earned on
the Property as of the date hereof to a segregated account held by you on behalf of Public Stockholders who have properly elected to have
their shares of Common Stock that were sold by the Company in the Offering (the “Public Shares”) redeemed by
the Company as described below. Capitalized terms used but not defined herein shall have the meanings set forth in the Trust Agreement.


 


The Company needs such funds
to pay the Public Stockholders who have properly elected to have their Public Shares redeemed by the Company in connection with a stockholder
vote to approve an amendment to the Company’s Amended and Restated Certificate of Incorporation to modify the substance or timing
of the ability of Public Stockholders to seek redemption in connection with an initial Business Combination or the Company’s obligation
to redeem 100% of the Public Shares if the Company has not consummated an initial Business Combination within such time as is described
in the Company’s Amended and Restated Certificate of Incorporation or to affect provisions of the Company’s Amended and Restated
Certificate of Incorporation relating to the Company’s pre-initial Business Combination activity or related stockholder rights.
As such, you are hereby directed and authorized to transfer (via wire transfer) such funds promptly upon your receipt of this letter to
a segregated account held by you on behalf of such Public Stockholders.


 


	 	Very truly yours,
	 	 
	 	Mount Rainier Acquisition Corp.
	 	 
	 	By  	 
	 	 	Name:
	 	 	Title:




 


cc:       A.G.P./Alliance Global Partners