Spur Gear Bore Diameter 3/4 in Hub Diameter 1.75 in Hub Projection 0.75 in Face Width 3/4 in Pitch Diameter 4 in Material Cast Iron 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