Features: Manufactured from specially formulated to high-temperature polymer and designed with deeper cogs on top and rounded cogs on the bottom. Faster and more consistent throttle response, higher speed and quicker throttle response at mid-speed acceleration. Greater secondary acceleration at high rpm's and as primary acceleration increases. Offers better performance during deceleration (more responsive engine braking). Designed to maximize the performance of high-horsepower engines. Tested and proven to be reliable at well over 12,000 rpm. Operates at a cooler running temperature. Provides more power to track. Belt length is measured by OC (Outer Circumference).. Belt width is measured by top width..