American Society for Testing and Materials (ASTM). Current edition approved Oct. 1, 2005. Published October 2005. Originally approved in 1978. Last previous edition approved in 2000 as B 643 – 00. 5 p. This specification establishes requirements for copper-beryllium alloy seamless tube in straight lengths. Copper Alloy UNS C17200 will be the alloy furnished whenever Specification B 643 is specified.