1. The model of the national standard pulley: generally there are O, A, B, C, D, E, and the national standard belt tooth is AX, BX, CX, DX, EX;
2. European standard pulley models: generally, there are SPZ, SPA, SPB, SPC, and European standard belt teeth include XPZ, XPA, XPB, XPC;
3. American standard pulley models: generally there are 3V, 5V, 8V, and American standard toothed models are 3VX, 5VX, 8VX;
The writing method of the European standard tapered pulley model is: SPA—100—01—1610—40