Flexible metallic hose assemblies manufactured to the following British Standard: BS 6501 : Part 1. Flexible metallic hose assemblies Part 1. Specification for corrugated hose assemblies. The flexible hose is stainless steel, the end fittings are carbon steel. These hoses are suitable for Natural Gas and LPG. They meet the requirements of BS 6896 Specification for installation of gas-fired overhead radiant heaters for industrial and commercial heating (2nd and 3rd family gases),provided the pressure class of hose is appropriate for the particular installation.