Form
of Underwriter’s Warrant


 


THE
REGISTERED HOLDER OF THIS PURCHASE WARRANT BY ITS ACCEPTANCE HEREOF, AGREES THAT IT WILL NOT SELL, TRANSFER OR ASSIGN THIS PURCHASE
WARRANT EXCEPT AS HEREIN PROVIDED AND THE REGISTERED HOLDER OF THIS PURCHASE WARRANT AGREES THAT IT WILL NOT SELL, TRANSFER, ASSIGN,
PLEDGE OR HYPOTHECATE THIS PURCHASE WARRANT FOR A PERIOD OF ONE HUNDRED EIGHTY DAYS FOLLOWING THE LATER OF THE EFFECTIVE DATE
(AS DEFINED BELOW) OR THE COMMENCEMENT OF SALES OF THE OFFERING TO WHICH THIS PURCHASE WARRANT RELATES TO ANYONE OTHER THAN (I)
MAXIM GROUP LLC OR AN UNDERWRITER OR A SELECTED DEALER IN CONNECTION WITH THE OFFERING, OR (II) A BONA FIDE OFFICER OR PARTNER
OF MAXIM GROUP LLC OR OF ANY SUCH UNDERWRITER OR SELECTED DEALER.


 


THIS
PURCHASE WARRANT IS NOT EXERCISABLE PRIOR TO [________________] [DATE THAT IS 180 DAYS FROM THE EFFECTIVE DATE OF THE OFFERING].
VOID AFTER 5:00 P.M., EASTERN TIME, [___________________] [DATE THAT IS FIVE YEARS FROM THE EFFECTIVE DATE OF THE OFFERING].


 


COMMON
STOCK PURCHASE WARRANT


 


For
the Purchase of [_____]1 Common Shares


of


PROLUNG,
INC.


 


1.
Purchase Warrant. THIS COMMON STOCK PURCHASE WARRANT (this “Purchase Warrant”)
CERTIFIES THAT, for good and valuable consideration, the receipt and sufficiency of which is hereby acknowledged, Maxim
Group LLC (“Holder”), as registered owner of this Purchase Warrant, is entitled, upon the terms and subject
to the limitations on exercise and the conditions hereinafter set forth, at any time or from time to time from [________________]
[DATE THAT IS ONE HUNDRED EIGHTY (180) DAYS FROM THE EFFECTIVE DATE OF THE OFFERING] (the “Commencement Date”),
and until at or before 5:00 p.m., Eastern time, on [____________] [DATE THAT IS FIVE YEARS FROM THE EFFECTIVE DATE OF THE OFFERING]
(the “Expiration Date”), but not thereafter, to subscribe for, purchase and receive, in whole or in part, up
to [____] shares of common stock (the “Shares”), par value $0.001 per share (the “Common Stock”),
of ProLung, Inc., a Delaware corporation (the “Company”), subject to adjustment as provided in Section 6 hereof.
If the Expiration Date is a day on which banking institutions are authorized or required by law or executive order to close, then
this Purchase Warrant may be exercised on the next succeeding day which is not such a day in accordance with the terms herein.
During the period ending on the Expiration Date, the Company agrees not to take any action that would terminate this Purchase
Warrant. This Purchase Warrant is initially exercisable at $[●] per Share [110% of the price of the shares sold in the
Offering]; provided, however, that upon the occurrence of any of the events specified in Section 6 hereof, the
rights granted by this Purchase Warrant, including the exercise price per Share and the number of Shares to be received upon such
exercise, shall be adjusted as therein specified. This Purchase Warrant is being issued in connection with a public offering of
shares of Common Stock pursuant to the Company’s registration statement on Form S-1 (File No.: 333-219735) (the “Offering”).
As used herein, the term “Exercise Price” shall mean the initial exercise price or the adjusted exercise price,
depending on the context. As used herein, “Effective Date” means the date on which the Company’s registration
statement on Form S-1 (File No.: 333-219735) was declared effective by the Commission (as defined below).


 





 






1
NTD: To be 7.0% of the total number of shares being sold in the offering.


 




    	 



     


    

 





2.
Exercise.


 


2.1
Exercise Form. In order to exercise this Purchase Warrant, the exercise form attached hereto must be duly executed and
completed and delivered to the Company, together with this Purchase Warrant and payment of the Exercise Price for the Shares being
purchased payable in cash by wire transfer of immediately available funds to an account designated by the Company or by certified
check or official bank check. If the subscription rights represented hereby shall not be exercised at or before 5:00 p.m., Eastern
time, on the Expiration Date, this Purchase Warrant shall become and be void without further force or effect, and all rights represented
hereby shall cease and expire.


 


2.2
Cashless Exercise. In lieu of exercising this Purchase Warrant by payment of cash or check payable to the order of the
Company pursuant to Section 2.1 above, Holder may elect to receive the number of Shares equal to the value of this Purchase Warrant
(or the portion thereof being exercised), by surrender of this Purchase Warrant to the Company, together with the exercise form
attached hereto, in which event the Company will issue to Holder Shares in accordance with the following formula:


 





	 	X	=	Y(A-B)	 
	 	A	 




 


	Where,	 	 	 
	 	X	=	The
    number of Shares to be issued to Holder;
	 	Y	=	The
    number of Shares for which the Purchase Warrant is being exercised;
	 	A	=	The
    fair market value of one Share; and
	 	B	=	The
    Exercise Price.


 


For
purposes of this Section 2.2, the fair market value of a Share is defined as follows:


 


	 	(i)	if
    the Shares are traded on a securities exchange, the value shall be deemed to be the closing price on such exchange on the
    trading day immediately prior to the exercise form being submitted in connection with the exercise of the Purchase Warrant;
    or
	 	 	 
	 	(ii)	if
    the Shares are actively traded over-the-counter, the value shall be deemed to be the closing bid on the trading day immediately
    prior to the exercise form being submitted in connection with the exercise of the Purchase Warrant; if there is no active
    public market in the United States, the value shall be the fair market value thereof, as determined in good faith by the Company’s
    Board of Directors.


 




    	-2-



     


    

 





3.
Transfer. The registered Holder of this Purchase Warrant agrees by his, her or its acceptance hereof, that such Holder
will not: (a) sell, transfer, assign, pledge or hypothecate this Purchase Warrant for a period of one hundred eighty (180) days
following the later of the Effective Date or the commencement of sales of the offering to which this Purchase Warrant relates
(the later of such dates, the “Transferability Date”) to anyone other than: (i) Maxim Group LLC (“Maxim”)
or an underwriter or a selected dealer participating in the Offering, or (ii) a bona fide officer or partner of Maxim or of any
such underwriter or selected dealer, in each case in accordance with FINRA Conduct Rule 5110(g)(1), or (b) cause this Purchase
Warrant or the securities issuable hereunder to be the subject of any hedging, short sale, derivative, put or call transaction
that would result in the effective economic disposition of this Purchase Warrant or the securities hereunder, except as provided
for in FINRA Rule 5110(g)(2). On and after the Transferability Date, transfers to others may be made subject to compliance with
or exemptions from applicable securities laws. In order to make any permitted assignment, the Holder must deliver to the Company
the assignment form attached hereto duly executed and completed, together with the Purchase Warrant and payment of all transfer
taxes, if any, payable in connection therewith. The Company shall within five (5) business days transfer this Purchase Warrant
on the books of the Company and shall execute and deliver a new Purchase Warrant or Purchase Warrants of like tenor to the appropriate
assignee(s) expressly evidencing the right to purchase the aggregate number of Shares purchasable hereunder or such portion of
such number as shall be contemplated by any such assignment. Notwithstanding the foregoing, the registered Holder of this Purchase
Warrant agrees by his, her or its acceptance hereof, that such Holder will not sell, transfer, assign, pledge or hypothecate this
Purchase Warrant.


 


4.
Registration Rights.


 


4.1
Demand Registration.


 


4.1.1
Grant of Right. Unless a registration statement covering the exercise of this Warrant and the sale of the Shares by the
Holder is in effect and available, the Company, upon written demand (a “Demand Notice”) of the Holder(s) of
at least 51% of the Purchase Warrants and/or the underlying Shares (“Majority Holders”), agrees to register,
on up to two separate occasions, all or any portion of the Shares underlying the Purchase Warrants (collectively, the “Registrable
Securities”) (each such registration, a “Demand Registration”). On each such occasion, the Company
will file a registration statement with the U.S. Securities and Exchange Commission (the “Commission”) covering
the Registrable Securities within sixty (60) days after receipt of a Demand Notice and use its reasonable best efforts to have
the registration statement declared effective promptly thereafter, subject to compliance with review by the Commission; provided,
however, that the Company shall not be required to comply with a Demand Notice if the Company has filed a registration
statement with respect to which the Holder is entitled to piggyback registration rights pursuant to Section 4.2 hereof and either:
(i) the Holder has elected to participate in the offering covered by such registration statement or (ii) if such registration
statement relates to an underwritten primary offering of securities of the Company, until the offering covered by such registration
statement has been withdrawn or until thirty (30) days after such offering is consummated. The demand for registration may be
made at any time after the Commencement Date and for a period of no more than five (5) years from the Effective Date or the commencement
of sales of the Offering in accordance with FINRA Rule 5110(f)(2)(G)(iv). The Company covenants and agrees to give written notice
of its receipt of any Demand Notice by any Holder(s) to all other registered Holders of the Purchase Warrants and/or the Registrable
Securities within ten (10) days after the date of the receipt of any such Demand Notice.


 




    	-3-



     


    

 


4.1.2
Terms. With respect to one Demand Registration, the Company shall bear all fees and expenses attendant to such Demand Registration,
but the Holders shall pay any and all underwriting commissions and the expenses of any legal counsel selected by the Holders to
represent them in connection with the sale of the Registrable Securities. With respect to one additional Demand Registration,
the Holders shall bear all fees and expenses attendant to such Demand Registration. The Company agrees to use its reasonable best
efforts to cause any filings required herein to become effective promptly and to qualify or register the Registrable Securities
in such States as are reasonably requested by the Holder(s); provided, however, that in no event shall the Company
be required to register the Registrable Securities in a State in which such registration would cause: (i) the Company to be obligated
to register or license to do business in such State or submit to general service of process in such State, or (ii) the principal
shareholders of the Company to be obligated to escrow their shares of capital stock of the Company. The Company shall cause any
registration statement filed pursuant to the demand right granted under Section 4.1.1 to remain effective for a period of at least
twelve (12) consecutive months after the date that the Holders of the Registrable Securities covered by such registration statement
are first given the opportunity to sell all of such securities. The Holders shall only use the prospectuses provided by the Company
to sell the shares covered by such registration statement, and will immediately cease to use any prospectus furnished by the Company
if the Company advises the Holder that such prospectus may no longer be used due to a material misstatement or omission. Notwithstanding
the provisions of this Section 4.1.2, the Holder shall be entitled to a demand registration under this Section 4.1.2 on up to
two (2) occasions, and such demand registration right shall terminate on the fifth anniversary of the Effective Date or the commencement
of sales of the Offering in accordance with FINRA Rule 5110(f)(2)(G)(iv).


 


4.2
“Piggy-Back” Registration.


 


4.2.1
Grant of Right. In addition to the demand right of registration described in Section 4.1 hereof, unless a registration
statement covering the exercise of this Warrant and the sale of the Shares by the Holder is in effect and available, the Holder
shall have the right, for a period of no more than seven (7) years from the Effective Date or the commencement of sales of the
Offering in accordance with FINRA Rule 5110(f)(2)(G)(v), to include the Registrable Securities as part of any other registration
of securities filed by the Company (other than in connection with a transaction contemplated by Rule 145(a) promulgated under
the Securities Act of 1933, as amended (the “Securities Act”), or pursuant to Form S-8 or any equivalent form);
provided, however, that if, solely in connection with any primary underwritten public offering for the account of
the Company, the managing underwriter(s) thereof shall, in its reasonable discretion, impose a limitation on the number of shares
of Common Stock which may be included in the Registration Statement because, in such underwriter(s)’ judgment, marketing
or other factors dictate such limitation is necessary to facilitate public distribution, then the Company shall be obligated to
include in such Registration Statement only such limited portion of the Registrable Securities with respect to which the Holder
requested inclusion hereunder as the underwriter shall reasonably permit. Any exclusion of Registrable Securities shall be made
pro rata among the Holders seeking to include Registrable Securities in proportion to the number of Registrable Securities sought
to be included by such Holders; provided, however, that the Company shall not exclude any Registrable Securities
unless the Company has first excluded all outstanding securities, the holders of which are not entitled to inclusion of such securities
in such Registration Statement or are not entitled to pro rata inclusion with the Registrable Securities.


 


4.2.2
Terms. The Company shall bear all fees and expenses attendant to registering the Registrable Securities pursuant to Section
4.2.1 hereof, but the Holders shall pay any and all underwriting commissions and the expenses of any legal counsel selected by
the Holders to represent them in connection with the sale of the Registrable Securities. In the event of such a proposed registration,
the Company shall furnish the then Holders of outstanding Registrable Securities with not less than thirty (30) days written notice
prior to the proposed date of filing of such registration statement. Such notice to the Holders shall continue to be given for
each registration statement filed by the Company until such time as all of the Registrable Securities have been sold by the Holder.
The holders of the Registrable Securities shall exercise the “piggy-back” rights provided for herein by giving written
notice within ten (10) days of the receipt of the Company’s notice of its intention to file a registration statement. Except
as otherwise provided in this Purchase Warrant, there shall be no limit on the number of times the Holder may request registration
under this Section 4.2.2; provided, however, that such registration rights shall terminate on the seventh anniversary
of the Effective Date or the commencement of sales of the Offering in accordance with FINRA Rule 5110(f)(2)(G)(v).


 




    	-4-



     


    

 


4.3
General Terms.


 


4.3.1
Indemnification. The Company shall indemnify the Holder(s) of the Registrable Securities to be sold pursuant to any registration
statement hereunder and each person, if any, who controls such Holders within the meaning of Section 15 of the Securities Act
or Section 20 (a) of the Securities Exchange Act of 1934, as amended (“Exchange Act”), against all loss, claim,
damage, expense or liability (including all reasonable attorneys’ fees and other expenses reasonably incurred in investigating,
preparing or defending against any claim whatsoever) to which any of them may become subject under the Securities Act, the Exchange
Act or otherwise, arising from such registration statement but only to the same extent and with the same effect as the provisions
pursuant to which the Company has agreed to indemnify the Underwriters contained in Section 7(a) of the Underwriting Agreement
between Maxim Group LLC, as the representative of the several Underwriters named therein in Schedule A attached thereto, and the
Company, dated as of [●], 2018 (the “Underwriting Agreement”). The Holder(s) of the Registrable Securities
to be sold pursuant to such registration statement, and their successors and assigns, shall severally, and not jointly, indemnify
the Company, against all loss, claim, damage, expense or liability (including all reasonable attorneys’ fees and other expenses
reasonably incurred in investigating, preparing or defending against any claim whatsoever) to which they may become subject under
the Securities Act, the Exchange Act or otherwise, arising from information furnished by or on behalf of such Holder(s), or their
successors or assigns, in writing, for specific inclusion in such registration statement to the same extent and with the same
effect as the provisions contained in Section 7(b) of the Underwriting Agreement pursuant to which the Underwriters have agreed
to indemnify the Company.


 


4.3.2
Exercise of Purchase Warrants. Nothing contained in this Purchase Warrant shall be construed as requiring the Holder(s)
to exercise their Purchase Warrants prior to or after the initial filing of any registration statement or the effectiveness thereof.


 


4.3.3
Documents Delivered to Holders. The Company shall furnish to each Holder participating in any of the offerings pursuant
to Sections 4.1 and 4.2 hereof and to each underwriter of any such offering, if any, a signed counterpart, addressed to such Holder
or underwriter, of: (i) if such registration includes an underwritten public offering, an opinion of counsel to the Company, dated
the date of the closing under any underwriting agreement related thereto, and (ii) if such registration includes an underwritten
public offering, a “cold comfort” letter dated the effective date of such registration statement and a letter dated
the date of the closing under the underwriting agreement, signed by the independent registered public accounting firm which has
issued a report on the Company’s financial statements included in such registration statement, in each case covering substantially
the same matters with respect to such registration statement (and the prospectus included therein) and, in the case of such accountants’
letter, with respect to events subsequent to the date of such financial statements, as are customarily covered in opinions of
issuer’s counsel and in accountants’ letters delivered to underwriters in underwritten public offerings of securities.
The Company shall also deliver promptly to each Holder participating in the offering requesting the correspondence and memoranda
described below and to the managing underwriter, if any, copies of all correspondence between the Commission and the Company,
its counsel or auditors and all memoranda relating to discussions with the Commission or its staff with respect to the registration
statement and permit each Holder and underwriter to do such investigation, upon reasonable advance notice, with respect to information
contained in or omitted from the registration statement as it deems reasonably necessary to comply with applicable securities
laws or rules of FINRA. Such investigation shall include access to books, records and properties and opportunities to discuss
the business of the Company with its officers and independent auditors, all to such reasonable extent and at such reasonable times
as any such Holder shall reasonably request in connection with the underwritten offering.


 




    	-5-



     


    

 


4.3.4
Underwriting Agreement. The Company shall enter into an underwriting agreement with the managing underwriter(s), if any,
selected by any Holders whose Registrable Securities are being registered pursuant to Section 4.1 and Section 4.2, which managing
underwriter shall be reasonably satisfactory to the Company. Such agreement shall be reasonably satisfactory in form and substance
to the Company, each Holder and such managing underwriters, and shall contain such representations, warranties and covenants by
the Company and such other terms as are customarily contained in agreements of that type used by the managing underwriter. The
Holders shall be parties to any underwriting agreement relating to an underwritten sale of their Registrable Securities and may,
at their option, require that any or all the representations, warranties and covenants of the Company to or for the benefit of
such underwriters shall also be made to and for the benefit of such Holders. Such Holders shall not be required to make any representations
or warranties to or agreements with the Company or the underwriters except as they may relate to such Holders, their Shares and
their intended methods of distribution.


 


4.3.5
Documents to be Delivered by Holder(s). Each of the Holder(s) participating in any of the foregoing offerings shall furnish
to the Company a completed and executed questionnaire provided by the Company requesting information customarily sought of selling
security holders.


 


4.3.6
Damages. Should the registration or the effectiveness thereof required by Sections 4.1 and 4.2 hereof be delayed by the
Company or the Company otherwise fails to comply with such provisions, the Holder(s) shall, in addition to any other legal or
other relief available to the Holder(s), be entitled to obtain specific performance or other equitable (including injunctive)
relief against the threatened breach of such provisions or the continuation of any such breach, without the necessity of proving
actual damages and without the necessity of posting bond or other security.


 


5.
New Purchase Warrants to be Issued.


 


5.1
Partial Exercise. Subject to the restrictions in Section 3 hereof and the other terms and conditions of this Purchase Warrant,
this Purchase Warrant may be exercised in whole or in part, at any time or from time to time, on any business day from the Commencement
Date until the Expiration Date. In the event of the exercise hereof in part only, upon surrender of this Purchase Warrant for
cancellation, together with the duly exercised exercise form and funds sufficient to pay the Exercise Price pursuant to Section
2.1 hereto, the Company shall cause to be delivered to the Holder without charge a new Purchase Warrant of like tenor to this
Purchase Warrant in the name of the Holder evidencing the right of the Holder to purchase the number of Shares purchasable hereunder
as to which this Purchase Warrant has not been exercised.


 


5.2
Lost Purchase Warrant. Upon receipt by the Company of evidence satisfactory to it of the loss, theft, destruction or mutilation
of this Purchase Warrant and of reasonably satisfactory indemnification or the posting of a bond, the Company shall execute and
deliver a new Purchase Warrant of like tenor and date. Any such new Purchase Warrant executed and delivered as a result of such
loss, theft, mutilation or destruction shall constitute a substitute contractual obligation on the part of the Company.


 




    	-6-



     


    

 


6.
Adjustments.


 


6.1
Adjustments to Exercise Price and Number of Securities. The Exercise Price and the number of Shares underlying the Purchase
Warrant shall be subject to adjustment from time to time as hereinafter set forth:


 


6.1.1
Share Dividends; Split Ups. If, after the date hereof, and subject to the provisions of Section 6.3 below, the number of
outstanding Shares is increased by a stock dividend payable in Shares or by a split up of Shares or other similar event, then,
on the effective day thereof, the number of Shares purchasable hereunder shall be increased in proportion to such increase in
outstanding Shares, and the Exercise Price shall be proportionately decreased.


 


6.1.2
Aggregation of Shares. If, after the date hereof, and subject to the provisions of Section 6.3 below, the number of outstanding
Shares is decreased by a consolidation, combination, reverse stock split or reclassification of Shares or other similar event,
then, on the effective date thereof, the number of Shares purchasable hereunder shall be decreased in proportion to such decrease
in outstanding Shares, and the Exercise Price shall be proportionately increased.


 


6.1.3
Replacement of Securities upon Reorganization, etc. In case of any reclassification or reorganization of the outstanding
Shares other than a change covered by Section 6.1.1 or 6.1.2 hereof or that solely affects the par value of such Shares, or in
the case of any merger or consolidation of the Company with or into another corporation (other than a merger or consolidation
in which the Company is the continuing corporation and that does not result in any reclassification or reorganization of the outstanding
Shares), or in the case of any sale or conveyance to another corporation or entity of the property of the Company as an entirety
or substantially as an entirety in connection with which the Company is dissolved, the Holder of this Purchase Warrant shall have
the right thereafter (until the expiration of the right of exercise of this Purchase Warrant) to receive upon the exercise hereof,
for the same aggregate Exercise Price payable hereunder (as adjusted pursuant to this Section 6.1.3) immediately prior to such
event, the kind and amount of shares of stock or other securities or property (including cash) receivable upon such reclassification,
reorganization, share reconstruction or amalgamation, or consolidation, or upon a dissolution following any such sale or transfer,
by a Holder of the number of Shares of the Company obtainable upon exercise of this Purchase Warrant immediately prior to such
event; and if any reclassification also results in a change in Shares covered by Section 6.1.1 or 6.1.2, then such adjustment
shall be made pursuant to Sections 6.1.1, 6.1.2 and this Section 6.1.3. The provisions of this Section 6.1.3 shall similarly apply
to successive reclassifications, reorganizations, share reconstructions or amalgamations, or consolidations, sales or other transfers.


 


6.1.4
Changes in Form of Purchase Warrant. This form of Purchase Warrant need not be changed because of any change pursuant to
this Section 6.1, and Purchase Warrants issued after such change may state the same Exercise Price and the same number of Shares
as are stated in the Purchase Warrants initially issued pursuant to this Agreement. The acceptance by any Holder of the issuance
of new Purchase Warrants reflecting a required or permissive change shall not be deemed to waive any rights to an adjustment occurring
after the Commencement Date or the computation thereof.


 


6.2
Substitute Purchase Warrant. In case of any merger or consolidation of the Company with or into another corporation (other
than a merger or consolidation which does not result in any reclassification or change of the outstanding Shares), the corporation
formed by such merger or consolidation shall execute and deliver to the Holder a supplemental Purchase Warrant providing that
the holder of each Purchase Warrant then outstanding or to be outstanding shall have the right thereafter (until the stated expiration
of such Purchase Warrant) to receive, upon exercise of such Purchase Warrant, the kind and amount of shares of stock and other
securities and property receivable upon such merger or consolidation, by a holder of the number of Shares of the Company for which
such Purchase Warrant might have been exercised immediately prior to such merger or consolidation, sale or transfer. Such supplemental
Purchase Warrant shall provide for adjustments which shall be identical to the adjustments provided for in this Section 6. The
above provision of this Section shall similarly apply to successive mergers or consolidations.


 




    	-7-



     


    

 


6.3
Elimination of Fractional Interests. The Company shall not be required to issue certificates representing fractions of
Shares upon the exercise of the Purchase Warrant, nor shall it be required to issue scrip or pay cash in lieu of any fractional
interests, it being the intent of the parties that all fractional interests shall be eliminated by rounding any fraction up or
down, as the case may be, to the nearest whole number of Shares or other securities, properties or rights.


 


7.
Reservation and Listing. The Company shall at all times reserve and keep available out of its authorized Shares, solely
for the purpose of issuance upon exercise of the Purchase Warrants, such number of Shares or other securities, properties or rights
as shall be issuable upon the exercise thereof. The Company covenants and agrees that, upon exercise of the Purchase Warrants
and payment of the Exercise Price therefor, in accordance with the terms hereby, all Shares and other securities issuable upon
such exercise shall be duly and validly issued, fully paid and non-assessable and not subject to preemptive rights of any shareholder.
As long as the Purchase Warrants shall be outstanding, the Company shall use its commercially reasonable efforts to cause all
Shares issuable upon exercise of the Purchase Warrants to be listed (subject to official notice of issuance) on all national securities
exchanges (or, if applicable, on the OTC Markets or any successor trading market) on which the Shares issued to the public in
the Offering may then be listed and/or quoted.


 


8.
Certain Notice Requirements.


 


8.1
Holder’s Right to Receive Notice. Nothing herein shall be construed as conferring upon the Holders the right to vote
or consent or to receive notice as a shareholder for the election of directors or any other matter, or as having any rights whatsoever
as a shareholder of the Company. If, however, at any time prior to the expiration of the Purchase Warrants and their exercise,
any of the events described in Section 8.2 shall occur, then, in one or more of said events, the Company shall give written notice
of such event at least fifteen days prior to the date fixed as a record date or the date of closing the transfer books for the
determination of the shareholders entitled to such dividend, distribution, conversion or exchange of securities or subscription
rights, or entitled to vote on such proposed dissolution, liquidation, winding up or sale. Such notice shall specify such record
date or the date of the closing of the transfer books, as the case may be. Notwithstanding the foregoing, the Company shall deliver
to each Holder a copy of each notice given to the other shareholders of the Company at the same time and in the same manner that
such notice is given to the shareholders.


 


8.2
Events Requiring Notice. The Company shall be required to give the notice described in this Section 8 upon one or more
of the following events: (i) if the Company shall take a record of the holders of its Shares for the purpose of entitling them
to receive a dividend or distribution payable otherwise than in cash, or a cash dividend or distribution payable otherwise than
out of retained earnings, as indicated by the accounting treatment of such dividend or distribution on the books of the Company,
(ii) the Company shall offer to all the holders of its Shares any additional shares of capital stock of the Company or securities
convertible into or exchangeable for shares of capital stock of the Company, or any option, right or warrant to subscribe therefor,
or (iii) a dissolution, liquidation or winding up of the Company (other than in connection with a consolidation or share reconstruction
or amalgamation) or a sale of all or substantially all of its property, assets and business shall be proposed. Failure to give
such notice shall not invalidate any such action.


 




    	-8-



     


    

 


8.3
Notice of Change in Exercise Price. The Company shall, promptly after an event requiring a change in the Exercise Price
pursuant to Section 6 hereof, send notice to the Holders of such event and change (“Price Notice”). The Price
Notice shall describe the event causing the change and the method of calculating same and shall be certified as being true and
accurate by the Company’s Chief Financial Officer.


 


8.4
Transmittal of Notices. All notices, requests, consents and other communications under this Purchase Warrant shall be in
writing and shall be deemed to have been duly made when hand delivered, or mailed by express mail or private courier service:
(i) if to the registered Holder of the Purchase Warrant, to the address of such Holder as shown on the books of the Company, or
(ii) if to the Company, to following address or to such other address as the Company may designate by notice to the Holders:


 


If
to the Holder:


 


Maxim
Group LLC


405
Lexington Avenue


New
York, NY 10174


Attn:
Jim Alfaro


Fax
No.: (212) 895-3783


 


If
to the Company:


 


ProLung,
Inc.


757
East South Temple, Suite 150


Salt
Lake City, Utah 84102


Attn:
Steven C. Eror


Fax
No: (801) 906-0333


 


9.
Miscellaneous.


 


9.1
Amendments. The Company and Maxim may from time to time supplement or amend this Purchase Warrant without the approval
of any of the Holders in order to cure any ambiguity, to correct or supplement any provision contained herein that may be defective
or inconsistent with any other provisions herein, or to make any other provisions in regard to matters or questions arising hereunder
that the Company and Maxim may deem necessary or desirable and that the Company and Maxim deem shall not adversely affect the
interest of the Holders. All other modifications or amendments shall require the written consent of and be signed by the party
against whom enforcement of the modification or amendment is sought.


 


9.2
Headings. The headings contained herein are for the sole purpose of convenience of reference, and shall not in any way
limit or affect the meaning or interpretation of any of the terms or provisions of this Purchase Warrant.


 


9.3.
Entire Agreement. This Purchase Warrant (together with the other agreements and documents being delivered pursuant to or
in connection with this Purchase Warrant) constitutes the entire agreement of the parties hereto with respect to the subject matter
hereof, and supersedes all prior agreements and understandings of the parties, oral and written, with respect to the subject matter
hereof.


 


9.4
Binding Effect. This Purchase Warrant shall inure solely to the benefit of and shall be binding upon, the Holder and the
Company and their respective successors, permitted assigns and legal representatives, and no other person shall have or be construed
to have any legal or equitable right, remedy or claim under or in respect of or by virtue of this Purchase Warrant or any provisions
herein contained.


 




    	-9-



     


    

 


9.5
Governing Law; Submission to Jurisdiction; Trial by Jury. This Purchase Warrant shall be governed by and construed and
enforced in accordance with the laws of the State of New York, without giving effect to conflict of laws principles thereof. The
Company hereby agrees that any action, proceeding or claim against it arising out of, or relating in any way to this Purchase
Warrant shall be brought and enforced in the New York Supreme Court, County of New York, or in the United States District Court
for the Southern District of New York, and irrevocably submits to such jurisdiction, which jurisdiction shall be exclusive. The
Company hereby waives any objection to such exclusive jurisdiction and that such courts represent an inconvenient forum. The Company
and the Holder agree that the prevailing party(ies) in any such action shall be entitled to recover from the other party(ies)
all of its reasonable attorneys’ fees and expenses relating to such action or proceeding and/or incurred in connection with
the preparation therefor. The Company (on its behalf and, to the extent permitted by applicable law, on behalf of its stockholders
and affiliates) and the Holder hereby irrevocably waive, to the fullest extent permitted by applicable law, any and all right
to trial by jury in any legal proceeding arising out of or relating to this Agreement or the transactions contemplated hereby.


 


9.6
Waiver, etc. The failure of the Company or the Holder to at any time enforce any of the provisions of this Purchase Warrant
shall not be deemed or construed to be a waiver of any such provision, nor to in any way affect the validity of this Purchase
Warrant or any provision hereof or the right of the Company or any Holder to thereafter enforce each and every provision of this
Purchase Warrant. No waiver of any breach, non-compliance or non-fulfillment of any of the provisions of this Purchase Warrant
shall be effective unless set forth in a written instrument executed by the party or parties against whom or which enforcement
of such waiver is sought; and no waiver of any such breach, non-compliance or non-fulfillment shall be construed or deemed to
be a waiver of any other or subsequent breach, non-compliance or non-fulfillment.


 


9.7
Execution in Counterparts. This Purchase Warrant may be executed in one or more counterparts, and by the different parties
hereto in separate counterparts, each of which shall be deemed to be an original, but all of which taken together shall constitute
one and the same agreement, and shall become effective when one or more counterparts has been signed by each of the parties hereto
and delivered to each of the other parties hereto. Such counterparts may be delivered by facsimile transmission or other electronic
transmission.


 


9.8
Exchange Agreement. As a condition of the Holder’s receipt and acceptance of this Purchase Warrant, Holder agrees
that, at any time prior to the complete exercise of this Purchase Warrant by Holder, if the Company and Maxim enter into an agreement
(“Exchange Agreement”) pursuant to which they agree that all outstanding Purchase Warrants will be exchanged
for securities or cash or a combination of both, then Holder shall agree to such exchange and become a party to the Exchange Agreement.


 


[Signature
Page Follows]


 




    	-10-



     


    

 


IN
WITNESS WHEREOF, the Company has caused this Purchase Warrant to be signed by its duly authorized officer as of the ____ day of
_______, 2018.


 


	PROLUNG, INC.	 
	 	 	 
	By:	        	 
	Name:	 	 
	Title:	 	 


 




    	-11-



     


    

 


[Form
to be used to exercise Purchase Warrant]


 


Date:
__________, 20___


 


The
undersigned hereby elects irrevocably to exercise the Purchase Warrant for ______ shares of Common Stock (the “Shares”)
of ProLung, Inc., a Delaware corporation (the “Company”), and hereby makes payment of $____ (at the rate of
$____ per Share) in payment of the Exercise Price pursuant thereto. Please issue the Shares as to which this Purchase Warrant
is exercised in accordance with the instructions given below and, if applicable, a new Purchase Warrant representing the number
of Shares for which this Purchase Warrant has not been exercised.


 


or


 


The
undersigned hereby elects irrevocably to convert its right to purchase ___ Shares of the Company under the Purchase Warrant for
______ Shares, as determined in accordance with the following formula:


 


	 	X	=	Y(A-B)	 
	A	 


 


	Where,	 	 	 
	 	X	=	The
    number of Shares to be issued to Holder;
	 	Y	=	The
    number of Shares for which the Purchase Warrant is being exercised;
	 	A	=	The
    fair market value of one Share which is equal to $_____; and
	 	B	=	The
    Exercise Price which is equal to $______ per share


 


The
undersigned agrees and acknowledges that the calculation set forth above is subject to confirmation by the Company and any disagreement
with respect to the calculation shall be resolved by the Company in its sole discretion.


 


Please
issue the Shares as to which this Purchase Warrant is exercised in accordance with the instructions given below and, if applicable,
a new Purchase Warrant representing the number of Shares for which this Purchase Warrant has not been converted.


 


Signature_______________________________


 


INSTRUCTIONS
FOR REGISTRATION OF SECURITIES


 


	Name:	 	 
	(Print
    in Block Letters)	 
	 	 	 
	Address:	 	 
	 	 	 
	 	 	 


 


NOTICE:
The signature to this form must correspond with the name as written upon the face of the Purchase Warrant without alteration or
enlargement or any change whatsoever, and must be guaranteed by a bank, other than a savings bank, or by a trust company or by
a firm having membership on a registered national securities exchange.


 




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