Features: Brand new and high quality Aluminum material: The timing belt pulley is made of high-quality aluminum, which is reliable and durable. Smooth and precise: precise tooth pitches, not prone to slipping, resulting in smooth and efficient operation. Easy installation:The timing belt pulley comes with screws on the side and comes packaged with an wrench. Widely used:Suitable for 3D printers, milling machines, drilling machines, gear shapers, hobbing machines, or other mechanical transmission applications. Quality assurance: please contact us and we will do our best to provide assistance. Specifications: Material: stainless steel Package Includes: 2Pcs 8mm Bore 36 Tooth Synchronous Wheels 2Pcs 8mm Bore 20 Tooth Synchronous Wheels 2Pcs Length 200mm Width 6mm Belts 4Pcs Screws 1PC Allen Wrench note: 1.No retail package. 2.Please allow 0-1cm error due to manual measurement. make sure you do not mind before you bid. 3.Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you.