model:MXL,XL,L,H,XH,XXH,T2.5,T5,T10,AT5,AT10,AT20, (HTD,STS,RPP,GT)2M,3M,5M,8M,14M,20M 45# Steel or Aluminium Material ,Nylon bar,plastic and other material Note when checking form and order pulley: 1. Belt and pulley of our company can be attachment or replacement of imported belt and pulley. 2. Please supply drawing when you order. We can also draw for clients as their supplied specification, hole, key way and width. 3. The tolerance of outside diameter, end bounce 7 wrap direction of pulley should conform to Form1,form 2 & form3. 4. Width of different specification of timing belt and pulley must conform to form4. 5. Outside diameter of pulleys and size should be as form's regulation. 6. We can also produce pulleys even sizes are not in the form. 7. The material of pulley mainly composed of carbon steel, if possible aluminum alloy nylon can also be employed; if external diameter is larger than 250 mm, iron is used.