This is the stock On/Off Assembly for the RT ULE Custom, RT Pro Retro Valve, X-Valve and old Automag RT markers. Comes complete with three O-rings, on/off top, on/off bottom and on/off pin .750 long.  Does not include the #00123 oring for bottom of flat on/off's.  Assembly comes partially together but will need to be lubricated before assembly in a gun.