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Exhibit 10.4

Execution Version

PRIVATE PLACEMENT

WARRANTS PURCHASE AGREEMENT

THIS PRIVATE PLACEMENT WARRANTS PURCHASE AGREEMENT, dated as of September 17,
2020 (this “Agreement”), is entered into by and between North Mountain Merger
Corp., a Delaware corporation (the “Company”), and North Mountain LLC, a
Delaware limited liability company (the “Purchaser”).

WHEREAS, the Company intends to consummate an initial public offering of the
Company’s units (the “Public Offering”), each unit consisting of one share of
the Company’s Class A common stock, par value $0.0001 per share (a “Share”), and
one-half of one redeemable warrant, each whole warrant exercisable for one Share
at an exercise price of $11.50 per Share, as set forth in the Company’s
registration statement on Form S-1 related to the Public Offering (the
“Registration Statement”); and

WHEREAS, the Purchaser now wishes to purchase an aggregate of 3,800,000 warrants
(or 4,145,000 warrants if the underwriters’ over-allotment option is exercised
in full) (the “Warrants”), each Warrant entitling the holder to purchase one
Share at an exercise price of $11.50 per Share.

NOW THEREFORE, in consideration of the mutual promises contained in this
Agreement and other good and valuable consideration, the receipt and sufficiency
of which are hereby acknowledged, the parties to this Agreement hereby,
intending legally to be bound, agree as follows:

AGREEMENT

Section 1.
Authorization, Purchase and Sale; Terms of the Warrants.

A.
Authorization of the Warrants.  The Company has duly authorized the issuance and
sale of the Warrants to the Purchaser.

B.
Purchase and Sale of the Warrants.

(i)
As payment in full for the 3,800,000 Warrants being purchased under this
Agreement, the Purchaser shall pay $3,800,000 (the “Purchase Price”), by wire
transfer of immediately available funds in accordance with the Company’s wiring
instructions, at least one (1) business day prior to the effective date of the
Registration Statement, or on such other date as the Company and the Purchaser
may agree.

(ii)
In the event that the underwriters’ over-allotment option is exercised in full,
the Purchaser shall purchase up to an additional 345,000 Warrants (the
“Additional Warrants”), in the same proportion as the amount of the
over-allotment option that is exercised, and simultaneously with such purchase
of Additional Warrants, as payment in full for the Additional Warrants being
purchased hereunder, and at least one (1) business day prior to the closing of
all or any portion of the over-allotment option, or on such other date as the
Company and the Purchaser may agree, the Purchaser shall pay $1.00 per
Additional Warrant, up to an aggregate amount of $345,000, by wire transfer of
immediately available funds in accordance with the Company’s wiring
instructions.

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(iii)
The closing of the purchase and sale of the Warrants shall take place
simultaneously with the closing of the Public Offering (the “Initial Closing
Date”).  The closing of the purchase and sale of the Additional Warrants, if
applicable, shall take place simultaneously with the closing of all or any
portion of the over-allotment option (such closing date, together with the
Initial Closing Date, the “Closing Dates” and each, a “Closing Date”).  The
closing of the purchase and sale of each of the Warrants and the Additional
Warrants shall take place at the offices of Paul, Weiss, Rifkind, Wharton &
Garrison LLP, 1285 Avenue of the Americas, New York, New York, 10019, or such
other place as may be agreed upon by the parties hereto.

C.
Terms of the Warrants.

(i)
The Warrants shall have their terms set forth in a Warrant Agreement to be
entered into by the Company and a warrant agent, in connection with the Public
Offering (a “Warrant Agreement”).

(ii)
At or prior to the time of the Initial Closing Date, the Company and the
Purchaser shall enter into a registration rights agreement (the “Registration
Rights Agreement”) pursuant to which the Company will grant certain registration
rights to the Purchaser relating to the Warrants and the Shares underlying the
Warrants.

Section 2.
Representations and Warranties of the Company.  As a material inducement to the
Purchaser to enter into this Agreement and purchase the Warrants, the Company
hereby represents and warrants to the Purchaser (which representations and
warranties shall survive the Closing Dates) that:

A.
Organization and Corporate Power.  The Company is a corporation duly organized,
validly existing and in good standing under the laws of the State of Delaware
and is qualified to do business in every jurisdiction in which the failure to so
qualify would reasonably be expected to have a material adverse effect on the
financial condition, operating results or assets of the Company.  The Company
possesses all requisite corporate power and authority necessary to carry out the
transactions contemplated by this Agreement and the Warrant Agreement.

B.
Authorization; No Breach.

(i)
The execution, delivery and performance of this Agreement and the Warrants have
been duly authorized by the Company as of the Closing Dates.  This Agreement
constitutes a valid and binding obligation of the Company, enforceable in
accordance with its terms.  Upon issuance in accordance with, and payment
pursuant to, the terms of the Warrant Agreement and this Agreement, the Warrants
will constitute valid and binding obligations of the Company, enforceable in
accordance with their terms as of the Closing Dates.

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(ii)
The execution and delivery by the Company of this Agreement and the Warrants,
the issuance and sale of the Warrants, the issuance of the Shares upon exercise
of the Warrants and the fulfillment of, and compliance with, the respective
terms hereof and thereof by the Company, do not and will not as of the Closing
Dates (a) conflict with or result in a breach of the terms, conditions or
provisions of, (b) constitute a default under, (c) result in the creation of any
lien, security interest, charge or encumbrance upon the Company’s capital stock
or assets under, (d) result in a violation of, or (e) require any authorization,
consent, approval, exemption or other action by or notice or declaration to, or
filing with, any court or administrative or governmental body or agency pursuant
to the certificate of incorporation or the bylaws of the Company (in effect on
the date hereof or as may be amended prior to completion of the contemplated
Public Offering), or any material law, statute, rule or regulation to which the
Company is subject, or any agreement, order, judgment or decree to which the
Company is subject, except for any filings required after the date hereof under
federal or state securities laws.

C.
Title to Securities.  Upon issuance in accordance with, and payment pursuant to,
the terms hereof and the Warrant Agreement, the Shares issuable upon exercise of
the Warrants will be duly and validly issued, fully paid and nonassessable. 
Upon issuance in accordance with, and payment pursuant to, the terms hereof and
the Warrant Agreement, the Purchaser will have good title to the Warrants and
the Shares issuable upon exercise of such Warrants, free and clear of all liens,
claims and encumbrances of any kind, other than (i) transfer restrictions
hereunder and under the other agreements contemplated hereby, (ii) transfer
restrictions under federal and state securities laws, and (iii) liens, claims or
encumbrances imposed due to the actions of the Purchaser.

D.
Governmental Consents.  No permit, consent, approval or authorization of, or
declaration to or filing with, any governmental authority is required in
connection with the execution, delivery and performance by the Company of this
Agreement or the consummation by the Company of any other transactions
contemplated hereby.

E.
Regulation D Qualification.  Neither the Company nor, to its knowledge, any of
its affiliates, officers, directors or beneficial stockholders of 20% or more of
its outstanding securities, has experienced a disqualifying event as enumerated
pursuant to Rule 506(d) of Regulation D under the Securities Act of 1933, as
amended (the “Securities Act”).

Section 3.
Representations and Warranties of the Purchaser.  As a material inducement to
the Company to enter into this Agreement and issue and sell the Warrants to the
Purchaser, the Purchaser hereby represents and warrants to the Company (which
representations and warranties shall survive the Closing Dates) that:

A.
Organization and Requisite Authority.  The Purchaser possesses all requisite
power and authority necessary to carry out the transactions contemplated by this
Agreement.

B.
Authorization; No Breach.

(i)
This Agreement constitutes a valid and binding obligation of the Purchaser,
enforceable in accordance with its terms, subject to bankruptcy, insolvency,
fraudulent conveyance, reorganization, moratorium and other laws of general
applicability relating to or affecting creditors’ rights and to general
equitable principles (whether considered in a proceeding in equity or law).

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(ii)
The execution and delivery by the Purchaser of this Agreement and the
fulfillment of and compliance with the terms hereof by the Purchaser does not
and shall not as of the Closing Dates conflict with or result in a breach by the
Purchaser of the terms, conditions or provisions of any agreement, instrument,
order, judgment or decree to which the Purchaser is subject.

C.
Investment Representations.

(i)
The Purchaser is acquiring the Warrants and, upon exercise of the Warrants, the
Shares issuable upon such exercise (collectively, the “Securities”), for the
Purchaser’s own account, for investment purposes only and not with a view
towards, or for resale in connection with, any public sale or distribution
thereof.

(ii)
The Purchaser is an “accredited investor” as such term is defined in Rule
501(a)(3) of Regulation D  under the Securities Act and the Purchaser has not
experienced a disqualifying event as enumerated pursuant to Rule 506(d) of
Regulation D under the Securities Act.

(iii)
The Purchaser understands that the Securities are being offered and will be sold
to it in reliance on specific exemptions from the registration requirements of
the United States federal and state securities laws and that the Company is
relying upon the truth and accuracy of, and the Purchaser’s compliance with, the
representations and warranties of the Purchaser set forth herein in order to
determine the availability of such exemptions and the eligibility of the
Purchaser to acquire such Securities.

(iv)
The Purchaser did not enter into this Agreement as a result of any general
solicitation or general advertising within the meaning of Rule 502(c) under the
Securities Act.

(v)
The Purchaser has been furnished with all materials relating to the business,
finances and operations of the Company and materials relating to the offer and
sale of the Securities which have been requested by the Purchaser.  The
Purchaser has been afforded the opportunity to ask questions of the executive
officers and directors of the Company.  The Purchaser understands that its
investment in the Securities involves a high degree of risk and it has sought
such accounting, legal and tax advice as it has considered necessary to make an
informed investment decision with respect to the acquisition of the Securities.

(vi)
The Purchaser understands that no United States federal or state agency or any
other government or governmental agency has passed on or made any recommendation
or endorsement of the Securities or the fairness or suitability of the
investment in the Securities by the Purchaser nor have such authorities passed
upon or endorsed the merits of the offering of the Securities.

(vii)
The Purchaser understands that: (a) the Securities have not been and are not
being registered under the Securities Act or any state securities laws, and may
not be offered for sale, sold, assigned or transferred unless (1) subsequently
registered thereunder or (2) sold in reliance on an exemption therefrom; and (b)
except as specifically set forth in the Registration Rights Agreement, neither
the Company nor any other person is under any obligation to register the
Securities under the Securities Act or any state securities laws or to comply
with the terms and conditions of any exemption thereunder.

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(viii)
The Purchaser has such knowledge and experience in financial and business
matters, knowledge of the high degree of risk associated with investments in the
securities of companies in the development stage such as the Company, is capable
of evaluating the merits and risks of an investment in the Securities and is
able to bear the economic risk of an investment in the Securities in the amount
contemplated hereunder for an indefinite period of time.  The Purchaser has
adequate means of providing for its current financial needs and contingencies
and will have no current or anticipated future needs for liquidity which would
be jeopardized by the investment in the Securities.  The Purchaser can afford a
complete loss of its investments in the Securities.

Section 4.
Conditions of the Purchaser’s Obligations.  The obligations of the Purchaser to
purchase and pay for the Warrants are subject to the fulfillment, on or before
the Closing Dates, of each of the following conditions:

A.
Representations and Warranties.  The representations and warranties of the
Company contained in Section 2 shall be true and correct at and as of the
Closing Dates as though then made.

B.
Performance.  The Company shall have performed and complied with all agreements,
obligations and conditions contained in this Agreement that are required to be
performed or complied with by it on or before the Closing Dates.

C.
No Injunction.  No litigation, statute, rule, regulation, executive order,
decree, ruling or injunction shall have been enacted, entered, promulgated or
endorsed by or in any court or governmental authority of competent jurisdiction
or any self-regulatory organization having authority over the matters
contemplated hereby, which prohibits the consummation of any of the transactions
contemplated by this Agreement or the Warrant Agreement.

D.
Warrant Agreement.  The Company shall have entered into a Warrant Agreement with
a warrant agent on terms satisfactory to the Purchaser (the “Warrant
Agreement”).

Section 5.
Conditions of the Company’s Obligations.  The obligations of the Company to the
Purchaser under this Agreement are subject to the fulfillment, on or before the
Closing Dates, of each of the following conditions:

A.
Representations and Warranties.  The representations and warranties of the
Purchaser contained in Section 3 shall be true and correct at and as of the
Closing Dates as though then made.

B.
Performance.  The Purchaser shall have performed and complied with all
agreements, obligations and conditions contained in this Agreement that are
required to be performed or complied with by the Purchaser on or before the
Closing Dates.

C.
No Injunction.  No litigation, statute, rule, regulation, executive order,
decree, ruling or injunction shall have been enacted, entered, promulgated or
endorsed by or in any court or governmental authority of competent jurisdiction
or any self-regulatory organization having authority over the matters
contemplated hereby, which prohibits the consummation of any of the transactions
contemplated by this Agreement or the Warrant Agreement.

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D.
Warrant Agreement.  The Company shall have entered into the Warrant Agreement.

Section 6.
Termination.  This Agreement may be terminated at any time after December 31,
2020 upon the election by either the Company or a Purchaser entitled to purchase
a majority of the Warrants upon written notice to the other parties if the
closing of the Public Offering does not occur prior to such date.

Section 7.
Survival of Representations and Warranties.  All of the representations and
warranties contained herein shall survive the Closing Dates.

Section 8.
Definitions.  Terms used but not otherwise defined in this Agreement shall have
the meaning assigned to such terms in the Registration Statement.

Section 9.
Miscellaneous.

A.
Successors and Assigns.  Except as otherwise expressly provided herein, all
covenants and agreements contained in this Agreement by or on behalf of any of
the parties hereto shall bind and inure to the benefit of the respective
successors of the parties hereto whether so expressed or not.  Notwithstanding
the foregoing or anything to the contrary herein, the parties may not assign
this Agreement, other than assignments by the Purchaser to affiliates thereof.

B.
Severability.  Whenever possible, each provision of this Agreement shall be
interpreted in such manner as to be effective and valid under applicable law,
but if any provision of this Agreement is held to be prohibited by or invalid
under applicable law, such provision shall be ineffective only to the extent of
such prohibition or invalidity, without invalidating the remainder of this
Agreement.

C.
Counterparts.  This Agreement may be executed simultaneously in two or more
counterparts, none of which need contain the signatures of more than one party,
but all such counterparts taken together shall constitute one and the same
agreement.

D.
Descriptive Headings; Interpretation.  The descriptive headings of this
Agreement are inserted for convenience only and do not constitute a substantive
part of this Agreement.  The use of the word “including” in this Agreement shall
be by way of example rather than by limitation.

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E.
Governing Law.  This Agreement and the rights and obligations of the parties
hereunder shall be construed in accordance with and governed by the laws of New
York applicable to contracts wholly performed within the borders of such state,
without giving effect to the conflict of law principles thereof.  The parties
hereto irrevocably submit to the exclusive jurisdiction of any federal court
sitting in the Southern District of New York or any state court located in New
York County, State of New York, over any suit, action or proceeding arising out
of or relating to this Agreement.  To the fullest extent they may effectively do
so under applicable law, the parties hereto irrevocably waive and agree not to
assert, by way of motion, as a defense or otherwise, any claim that they are not
subject to the jurisdiction of any such court, any objection that they may now
or hereafter have to the laying of the venue of any such suit, action or
proceeding brought in any such court and any claim that any such suit, action or
proceeding brought in any such court has been brought in an inconvenient forum.

F.
Amendments.  This letter agreement may not be amended, modified or waived as to
any particular provision, except by a written instrument executed by all parties
hereto.

[Signature page follows]

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IN WITNESS WHEREOF, the parties hereto have executed this Agreement to be
effective as of the date first set forth above.

 
COMPANY:
         
NORTH MOUNTAIN MERGER CORP.
         
By:
/s/ Charles B. Bernicker
   
Name: Charles B. Bernicker
   
Title:   Chief Executive Officer
         
NORTH MOUNTAIN LLC
           
By: Harbour Reach Holdings LLC,
its managing member
             
By: Netherton Investments Limited,
its managing member
         

By:
/s/ Mike Bell
   

Name: Mike Bell
   

Title:   Director

[Signature Page to Private Placement Warrants Purchase Agreement]

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