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XY Motor Pulley for 4mm Shaft

This is the aluminum pulley that attaches to the Nema 17 motor in the CupCake CNC X and Y Stage Assembly.

Please note -- this is the older 4mm size and will NOT fit the NEMA 17 Hybrid Motor.

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