This standard specifies the types and dimensions of cylindrical and recessed lamp caps. This standard applies to the design and production of electric light source products that use the lamp caps specified in this part as lamp accessories, and also applies to the design of other electric light source products.
GB 1406.4-2003 history
2008GB/T 1406.4-2008 Types and dimensions of lamp caps.Part 4: Miscellaneous caps
2003GB 1406.4-2003 Types and dimensions of lamp caps--Part 4: Shell and recessed caps
GB 1406.4-2003 Types and dimensions of lamp caps--Part 4: Shell and recessed caps was changed to GB/T 1406.4-2008 Types and dimensions of lamp caps.Part 4: Miscellaneous caps.