This Martin DF-1 type timing pulley is suitable for use with 1/2" and 3/4" wide trapezoidal tooth belts in power transmission applications that require synchronous rotation. It is made of high carbon steel for tensile strength and hardness and has a Light (L) pitch profile. This pulley has a plain bore and mounts to a drive shaft using set screws. Double flanges on the pulley resist side thrust and maintain belt contact. Timing pulleys are a type of drive pulley and are used in a wide range of mechanical and electronic drives, including automotive and printing industries.Pulley drive systems consist of two or more pulleys that connect with a belt to transmit mechanical power across greater distances than systems that use gears. Pulleys (sheaves) are available in different types: V-belt, timing, round, or flat. Pulleys must match the belts that connect them (timing pulleys with trapezoidal grooves require a belt with trapezoidal teeth) and engage either on the sides of the pulley flange (classical V-belts, narrow V-belts, or round belts), on the flat outer diameter of the pulley (flat belts), or in pulley grooves that match belt teeth (timing belts, synchronous belts, or curvilinear belts). Pulleys are made of various materials, including cast iron, steel, aluminum, polycarbonate resin thermoplastic, and nylon, and they can meet a broad range of requirements, including increased torque, resistance to wear, and light weight. Pulleys are used in drive designs in the automotive, appliance, agriculture, textile, printing, mining, and office equipment industries.Martin Sprocket & Gear manufactures power transmission products, material handling components, and industrial hand tools. The company, founded in 1951 and headquartered in Arlington, TX, meets International Organization for Standardization (ISO) standard 9001:2008.