X0306 4 2018-05-14 0 0001693256 Select Energy Services, Inc. WTTR 0001698213 Gillette Gary 515 POST OAK BLVD., STE. 200 HOUSTON TX 77027 0 1 0 0 See Remarks Class A Common Stock 2018-05-14 4 J 0 32883 0 A 45688 D Reflects the distribution from SES Legacy Holdings, LLC, to the Reporting Person, of 32,883 limited liability company units of SES Holdings, LLC (each, an "SES Holdings LLC Unit") and 32,883 shares of Class B common stock of the Issuer and the exchange of such SES Holdings LLC Units and Class B common stock for an equal number of shares of Class A common stock of the Issuer. Chief Administrative Officer & Senior VP /s/ Gary Gillette by Adam R. Law, as Attorney-in-Fact 2018-05-16