This is Aluminum GT2 Timing Pulley 30 Teeth 5mm Bore For 6mm Belt. For precise motion control, GT2 belts and pulleys offer excellent precision at a great price. This pulley is meant for use with GT2 6mm wide belts only – MXL belts will slip due to the different tooth profile.
This pulley has 30 teeth and a 5mm inner bore. Two set screws can be used to attach it firmly to any 5mm diameter shaft. Full aluminum construction means these are very light and very durable.