Exhibit 10.4


 


SENTINEL
ENERGY SERVICES INC.


1000 Louisiana Street, Suite 3850


Houston, TX 77002


 


November
2, 2017


 


Sentinel
Management Holdings, LLC


1000 Louisiana Street, Suite 3850


Houston, TX 77002


 


	 	Re:	Administrative Services Agreement




 


Gentlemen:


 


This
letter agreement by and between Sentinel Energy Services Inc. (the “Company”) and Sentinel Management Holdings, LLC
(“Sponsor”), dated as of the date hereof, will confirm our agreement that, commencing on the date the securities of
the Company are first listed on the NASDAQ Capital Market (the “Listing Date”), pursuant to a Registration Statement
on Form S-1 and prospectus filed with the Securities and Exchange Commission (the “Registration Statement”) and continuing
until the earlier of the consummation by the Company of an initial business combination or the Company’s liquidation (in
each case as described in the Registration Statement) (such earlier date hereinafter referred to as the “Termination Date”):


 


(i)
Sponsor shall make available to the Company, at 1000 Louisiana Street, Suite 3850, Houston, TX 77002 (or any successor
location of Sponsor), certain office space, utilities, secretarial support and administrative services as may be reasonably
required by the Company. In exchange therefor, the Company shall pay Sponsor the sum of $10,000 per month on the Listing Date
and continuing monthly thereafter until the Termination Date; and


 


Sponsor
hereby irrevocably waives any and all right, title, interest, causes of action and claims of any kind (each, a “Claim”)
in or to, and any and all right to seek payment of any amounts due to it out of, the trust account established for the benefit
of the public stockholders of the Company and into which substantially all of the proceeds of the Company’s initial public
offering will be deposited (the “Trust Account”), and hereby irrevocably waives any Claim it may have in the future
as a result of, or arising out of, this letter agreement, which Claim would reduce, encumber or otherwise adversely affect the
Trust Account or any monies or other assets in the Trust Account, and further agrees not to seek recourse, reimbursement, payment
or satisfaction of any Claim against the Trust Account or any monies or other assets in the Trust Account for any reason whatsoever.


 


This
letter agreement constitutes the entire agreement and understanding of the parties hereto in respect of its subject matter and
supersedes all prior understandings, agreements, or representations by or among the parties hereto, written or oral, to the extent
they relate in any way to the subject matter hereof or the transactions contemplated hereby.


 


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


 


No
party hereto may assign either this letter agreement or any of its rights, interests, or obligations hereunder without the prior
written approval of the other party. Any purported assignment in violation of this paragraph shall be void and ineffectual and
shall not operate to transfer or assign any interest or title to the purported assignee.


 


This
letter agreement, the entire relationship of the parties hereto, and any litigation between the parties (whether grounded in contract,
tort, statute, law or equity) shall be governed by, construed in accordance with, and interpreted pursuant to the laws of the
State of New York, without giving effect to its choice of laws principles.


 


[Signature
page follows]


 






     


     


    

 





	 	Very
    truly yours,
	 	 
	 	SENTINEL
    ENERGY SERVICES INC.
	 	 
	 	By:
    	 /s/
    Kent Jamison
	 	 	Name:
    Kent Jamison
	 	 	Title:
    Secretary


 


AGREED
TO AND ACCEPTED BY:


 


SENTINEL
MANAGEMENT HOLDINGS, LLC


 


	By:
    	 /s/
    Charles S. Leykum	 
	 	Name:
    Charles S. Leykum	 
	 	Title:
    Chief Executive Officer 	 


 


[Signature
Page to Administrative Services Agreement]