The 117X fittings are a retro-fit type fitting designed to be added on to existing structures without the need to disassemble.
The 117X fittings comes complete with 2 socket pieces and 2 plate pieces which enable each kit to be used to make one of the two possible assemblies illustrated below.
Each kit comes complete with bolts and set screws.
This fitting is only compatible with the D48 size range.