3/8" Duplex - Pilot Bore A full range of sprockets in both Taper Bore and Pilot Bore are available in Simplex, Duplex and Triplex styles. We also carry a complete range of taper bore bushes and keyway steels to suit. • All sprockets are manufactured to exacting standards and specification. • Taper bore bush versions allow for quick and simple installation without the need to machine the sprocket. • Boring and keyway service for pilot bore sprockets is available on request. • Cast iron sprockets are also available on request.