10L050F(PB) Dunlop / Optibelt Timing Belt Pilot Bore Pulley
Timing pulleys are indicated by a conventional code consisting of 3 groups. The first group shows number of teeth. The second group shows the pitch. The third group shows the belt width for which the pulley has to be used:
XL, L, H, XH & XXH pulleys, the belt width is in hundred of an inch (100 =1 inch)
HTD, T2,5, T5 & T10 pulleys the belt width is in mm.