[Signature Page Follows.]

Weatherford Artificial Lift Systems, Inc.

2000 St. James Place

Houston, Texas 77056

Attention: Legal Contracts

Reference is hereby made to that certain Supply Agreement dated as of January 11, 2010, as amended by that certain First Amendment to Supply Agreement, dated as of March 5, 2014, as amended by that certain Amended and Restated First Amendment to Supply Agreement, dated as of March 5, 2014, as amended by that certain Second Amendment to Supply Agreement, dated as of August 8, 2014 (as amended, the “Supply Agreement”), by and between Weatherford U.S., L.P., on behalf of itself and its affiliates including Weatherford Artificial Lift Systems, L.L.C. (f/k/a Weatherford Artificial Lift Systems, Inc.) (collectively with its affiliates, “Weatherford”), and Hi-Crush Operating LLC, on behalf of itself and its affiliates (collectively with its affiliates, “Supplier” and, together with Weatherford, the “Parties”). All capitalized terms used but not defined herein shall have the meanings ascribed to such terms in the Supply Agreement.

The Parties hereby agree that, during the period commencing on *** (the “Interim Term Effective Date”) and ending *** (such ***-month period, the “Interim Term”), the following terms and conditions shall apply:

The Parties hereby further agree that, at the end of the Interim Term, provided that Weatherford has fully complied with its obligations set forth in this letter agreement:

Except as expressly set forth herein, the Supply Agreement is and will remain unmodified and in full force and effect, including without limitation with respect to the volume requirements contained in the Supply Agreement in effect as of the date hereof. Each future reference to the Supply Agreement will refer to the Supply Agreement as modified by this letter agreement.

All information contained in this letter agreement, including the existence of such letter agreement, is deemed confidential and shall not be disclosed to any third party; provided that the provisions set forth in Article 5 of the Supply Agreement shall apply to the information contained herein as if such information was Confidential Information. This letter agreement may be executed in any number of counterparts, each of which shall be deemed to be an original instrument, but all of which taken together shall constitute one instrument. A signature page to this letter agreement that contains a copy of a party’s signature and that is sent by such party or its agent with the apparent intention (as reasonably evidenced by the actions of such party or its agent) that it constitute such party’s execution and delivery of this letter agreement, including a document sent by facsimile transmission or by email in portable document format (pdf), shall have the same effect as if such party had executed and delivered an original of this letter agreement. This letter agreement shall be governed by and construed in accordance with the internal laws of the State of Texas without regard to conflict of law principles and shall be binding on the parties hereto and their successors and assigns.

Best regards,