... #Steel, Aluminum Alloys 3.Type:Trapezoid tooth,T synchronization ,HTD(STD)synchronization Timing Belt Pully Specification:Trapezoid tooth MXL,XL,L ... pulleys T2.5,T5,T10,T20,AT5,AT10,AT20 HTD(STD) synchronization pulleys RPP2M,3M,5M,8M,14M,20M HTD/STD2M ... and constant ratio, can work without sliding 3.It's stable, low noise 4.High transmission efficiency, save energy obviously 5 ...