Specifications include, but are not limited to: The Clark County School District, herein referred to as District, is accepting proposals for presorting the District’s mail and delivering it to the main United States Post Office located at 1001 E. Sunset Road, Las Vegas, NV 89199 ; The District currently sends out approximately 5.9 million pieces of mail annually, with first-class mail accounting for 75 percent of the volume and non-profit bulk mail accounting for 25 percent. Over 90 percent of all mail is distributed within Clark County. Provide zip code sorting services for: letter, postcard, and flats to achieve the lowest postal rates. Be CASS (Coding Accuracy Support System)-Certified and utilize the system. Meet U.S.P.S. MERLIN (Mail Evaluation Readability Look Instrument) requirements. Correct, as required, postage amounts for mail pieces which are not correctly metered to meet current U.S. Postage requirements.