Spur Gear Bore Diameter 1/2 in Hub Diameter 0.75 in Hub Projection 0.5 in Face Width 3/4 in Pitch Diameter 1 in Material Steel Pressure Angle 14.5 Degrees Compatible Gear Rack Grainger Part Number 1L901 1L902 Compatible Gear Rack Manufacturer Part Number L514-6 L515-6 Diametral Pitch 12 Keyway No