3 Prong, 11 mm ID with 4 mm key way x .75" wide Adapter for freewheel sprockets with 16 teeth & up that have 1.375 x 24 tpi OD CW - right hand threads.
You can use the solid 3 prong 16, 18, 20 & 22 tooth sprockets that are 1/2" x 3/32".
You can use a Track Cog sprocket that has 12 to 20 teeth as the 2nd range and to hold the 3 prong sprocket on.
You could use a Track Cog and Freewheel.
These will have a half round keyway cut that works great with your 4 mm square key.
You can use a 1.375 x 24 tpi right hand lock ring to hold the 3 prong sprocket in place.
You can also put a 3 prong solid sprocket, use a 1-1/2" External Retaining Ring as a spacer and thread on a 1.375 x 24 Freewheel Sprocket.
( 11mm with 4mm )
May be used with some: eZip, Currie, iZip gear reduction motor so they can freewheel. UniteMY1018 Electric Motor, MY1018, MY1018z, Unite, XYD-16
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