3/4" ID x 1/2" wide with 3/16" keyway Adapter for freewheel sprockets and Track Cogs that have 1.37 x 24 tpi CW- Right hand threads.
Held in place by two 3/4” Ext. snap rings or use shaft collars.
Uses a 3/16" x 3/16" x 1/2" key way.
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