PEM premium light weight quick change gears are REM finished to run cooler. They are manufactured from high strength alloy steel. They are heat treated for strength and longevity. These lightened gears are specially designed to run smoother and last longer than std gears. 1.5 lbs. lighter decreases your rotating weight. 10 spline gears - Fits Bulldog (DMI), Franklin, Tiger, Winters, Halibrand and other quick change rear ends.