These gears are made of high quality billet aluminum are designed for maximum tuning of engine horsepower and torque. Each gear has steel sleeved bolts that hold the set positions time after time. This design allows the user to torque down the bolts without fear of stripping the gears. The gears also have a unique center cut which keeps the timing belt on the center of the gears and prevents premature timing belt wear. Gears are available in anodized red and blue.