Martin timing pulleys are manufactured to extremely close specifications and are stocked in minimum plain bore, taper bushed, QD bushed styles depending on size and pitch. Synchronous sprockets are non-slip toothed drives that require no lubrication. These sprockets have a wide speed range, are very efficient and make less noise than chain drives. Teeth on the belts are molded to conform with and engage the teeth on a mating sprocket. Martin Stock Timing Pulley, Solid Type DF-1, Minimum Plain/Reborable Bore, 5/8 to 1-5/8 in Bore Dia, 2.835 in Outside Dia, 2.865 in, 24 Grooves, 3/8 in Pitch, 1.062 in Face Width, 3-7/64 in Flange Dia, 2-1/4 in Hub Dia, 3/4 in Hub Projection, 2 in Overall Length, For Use With: 1 in W Type L Belt, Steel