Weld-on hubs are made of low carbon steel for good welding compatibility. They are useful for welding into fan rotors, impellers, agitators, etc., which require secure mounting to the shaft. A standard type is available in addition to one that is specifically designed for use in the end disc of a conveyor pulley. Dodge Weld-On Hub, QD Type 2/SDS-A, 2.18 in Bore Dia, 3-1/2 in Outside Dia, 2.69 in Bolt Circle Dia, 3 Bolt Holes, 3/4 in Overall Length, Steel For use with type SDS bushing