[Code of Federal Regulations] [Title 48, Volume 4] [Revised as of October 1, 2006] From the U.S. Government Printing Office via GPO Access [CITE: 48CFR316.603] [Page 49] TITLE 48--FEDERAL ACQUISITION REGULATIONS SYSTEM CHAPTER 3--HEALTH AND HUMAN SERVICES PART 316_TYPES OF CONTRACTS--Table of Contents Subpart 316.6_Time-and-Materials, Labor-Hour, and Letter Contracts Sec. 316.603 Letter contracts.