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XY Motor Pulley for 5mm Shaft

Timing Pulley for the Thing-O-Matic® XY Axes, uses #4-40 set screw - 3/16" bored for 5mm motor shaft
Timing Pulley for the Thing-O-Matic® XY Axes, uses #4-40 set screw - 3/16" bored for 5mm motor shaft. This is the right size pulley for the new NEMA 17 Hybrid Stepper Motors, but will not fit the NEMA 17s we shipped before May 2011.

If you have any doubts about which pulley you need, measure your motor shaft with calipers or contact MakerBot® tech support.