Specifies material and dimensional requirements for seamless or electric resistance welded tubes intended for use as water bore casing. It covers six sizes specified by outside diameter, from 101.6 mm and 323.8 mm, providing for bevelled and welded joints in all sizes and for threaded and coupled joints in sizes up to 219.1 mm outside diameter. American National Standard Pipe Threads are used, and the Standard includes details of an obsolete thread formerly known as 44 in nominal pipe size. Minimum joint strengths of threaded and coupled casing are also given.