Specifications for Belt Size 512-8M-12 Cross References Numbers: 512-8M,  512-8M-12,  512-8M/12 Number of Teeth 64 *Length of Belt 512mm or ~20-1/8" Peak to Peak Distance Between Two Adjacent Belt Teeth 8mm or ~5/16" Width of Belt 12mm or ~7/16"

*Length of belt is the overall size of the belt's loop measured as if the belt were cut between two adjacent teeth and laid out on a flat surface.