Timing pulleys hts taper bore & pilot bore pitch sizes: 3m, 5m, 8m, 14m, 20m iso classical taper bore & pilot bore pitch sizes: mxl, xl, l, h, xh din metric pitch sizes: t2.5, t5, t10, t20, at5, at10, at20 supertorque pitch sizes: s4.5m, s5m, s8m, s14