... Standard:GB,JIS,BS,DIN,ANSI.5) Sizes & Sorts:Small sprocket,big sprocket;Single line,Double lines and more lines ... sprockets,Motorcycle sprockets,Bike sprockets,Idler Sprockets. 3.Further Machining Parts & Machinery Parts' Features: 1.Raw material & material status:Grey iron ... ,Copper alloy etc.2.The sorts of the machining parts/machinery parts:Pulley,Belt pulley,Synchronous belt pulley;Sheave;Gear, ...