Width               .4375 (3/8")

Center bore     .5" (1/2") keyed

Dual keyway   .125" (1/8")

Material            Nylon,  reduces vibration and noise

Part umber:  M6-165

Brand new made in US out of Nylon - tough and flexible plastic.

Nylon naturally slippery, no lubrication required.

Package include two spacers.