Pulleys are produced by automatic machining of the high precision lathe, with machining error within 0.005 mm. smooth motion, high printing precision, low noise, can greatly improve the printing speed. Perfect for 3d printers: Creality CR-10, CR-10S, tevo tarantula, CNC hybrid router, 8020 3030, and so on. Adopt this pulley bearing adopts bearings of motor grade, rust-resistant, wear-resistant, excellent friction resistance and operates smoothly.