Cylinder Split ring Western 64650 Fisher 20118K Meyer 07773 1-1/2" Cylinder

This is the Factory Western / Fisher Split ring # 64650 or 20118K . Also the same as a Meyer 07773.

This is the metal ring inside the cylinder that runs along the tube.

This is used on many of the common 1.5" cylinders 

Thius is for a 1/4" thick Groove , If you have the small groove you either need snap ring 25203 or the spring steel 48415.