Gates T312RB Blue Racing Timing Belt Belts are precision ground, not cut, so they fit the pulley with absolute perfection 104 Teeth, .866 inch(22mm) top width, .375 inch(9.5mm) pitch, 39 inch(991mm) 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