Gates T199RB Blue Racing Timing Belt Belts are precision ground, not cut, so they fit the pulley with absolute perfection 163 Teeth, 1.051 inch(27mm) top width, .315 inch(8mm) pitch, 51.338 inch(1304mm) pitch Length of stock belts Durable nylon fiber provides extra wear resistance, doubling tooth strength Aramid reinforcement in a patented EPDM compound for three times the heat resistance and durability of standard belt Patented EPDM compound gives Gates Racing belts extended service life