Joinder to Letter Agreement. Transferee hereby agrees to be bound by paragraph 6(b), paragraph 7(a) (subject to paragraph 7(c)) and paragraphs 11 through 16 of the Letter Agreement; in each case, to the same extent as if Transferee were an original party to the Letter Agreement (but solely for the purpose of the provisions of the Letter Agreement specified above and solely with respect to the Transferee Conversion Shares).

Joinder to Sponsor Agreement. Transferee hereby agrees to be bound by:

Letter Agreement. On the terms of this Amendment and subject to the satisfaction of the conditions precedent set forth in [Section 4] above, the Required Lenders acknowledge and agree that the Administrative Agent is authorized to enter into a letter agreement in connection with the sale of Receivables and Related Assets, in the form attached hereto as [Exhibit A].

Joinder – Crestview Investor I JOINDER TO SPONSOR AGREEMENT AND LETTER AGREEMENT This Joinder to Sponsor Agreement and Letter Agreement, dated as of ​ (this “Joinder”), is executed by Crestview III USWS, L.P., a Delaware limited partnership (“Transferee”), in favor of U.S. Well Services, Inc., a Delaware corporation (formerly Matlin & Partners Acquisition Corporation) (the “Company”), pursuant to [Section 3(d)] of the Sponsor Agreement (as defined below) and paragraph 7(c) of the Letter Agreement (as defined below). Each capitalized term used and not otherwise defined in this Joinder has the meaning given to such term in the Sponsor Agreement.

“Loan Documents” means this Agreement, each Note, each Issuer Document, each Guarantor Joinder Agreement, each Co-​ Joinder Agreement and the Fee Letter.

“Fee Letter” means that certain fee letter dated as of ​ between the Borrower and the Lead Arrangers (as amended by that certain Joinder Agreement to Project Eagle/Patriot Commitment Letter, dated as of ​ between the Borrower and the Lead Arrangers and as further amended by that certain Amended and Restated Joinder Agreement to Project Eagle/Patriot Commitment Letter, dated as of ​ between the Borrower and the Lead Arrangers).

Comfort Letter. On or prior to # the date of this Agreement, which is on or prior to the date of the first Issuance Instruction or the first Forward Placement Notice and # each Triggering Event Date with respect to which the Company is obligated to deliver a certificate pursuant to [Section 4(a)(xv)] for which no waiver is applicable and excluding the date of this Agreement, the Company shall cause Deloitte & Touche LLP, the independent registered public accounting firm who has audited the financial statements included or incorporated by reference in the Registration Statement and the Prospectus, to furnish the Agent and the Forward Purchaser a comfort letter, dated the date of delivery, in form and substance reasonably satisfactory to the Agent and its counsel and the Forward Purchasers and its counsel, substantially similar to the form previously provided to the Agent and its counsel and the Forward Purchasers and its counsel; provided, however, that any such comfort letter will only be required on the Triggering Event Date specified to the extent that it contains financial statements filed with the Commission under the Exchange Act and incorporated or deemed to be incorporated by reference into a Registration Statement or a Prospectus that have not previously been covered by a comfort letter delivered pursuant to this [Section 4(a)(xvii)]. If requested by the Agent or the Forward Purchaser, the Company shall also cause a comfort letter to be furnished to the Agent and the Forward Purchaser within ten (10) Trading Days of the date of occurrence of any material transaction or event requiring the filing of a current report on Form 8-K containing material amended financial information of the Company, including a restatement of the Company’s financial statements. The Company shall not be required to furnish more than one comfort letter hereunder per calendar quarter.

Fee Letter. The Parent Borrower shall pay to BofA Securities and the Domestic Administrative Agent for their own respective accounts, in Dollars, fees in the amounts and at the times specified in the Fee Letter. Such fees shall be fully earned when paid and shall be non-refundable for any reason whatsoever.

Comfort Letter. The Agent shall have received the Comfort Letter required to be delivered pursuant [Section 7(n)] on or before the date on which such delivery of such letter is required pursuant to [Section 7(n)].

Fee Letter. Agent shall have received that certain Third Amended and Restated Fee Letter, by and between Borrower and Agent, dated as of even date herewith (the “Third Amended and Restated Fee Letter”), duly executed by Borrower;