When a particular phase relationship is required between two parts of a machine, the angle adjusting hub provides quick, accurate and positive phase adjustment. Without the angle adjusting hub, phase relationship of parts requires extremely accurate machining of components as one tooth of a sprocket or gear is usually too coarse an adjustment. Browning® Synchro-Angle Adjusting Hub, 3/8 to 1 in Bore, 2-7/8 in OD, 2-7/16 in Pilot Diameter, 2-1/8 in Diameter Bolt Circle, 3 Bolt Holes, 2-1/8 in Overall Length