Performance Machine Spoke Mount Rotors are CNC precision ground to ensure a flat and parallel surface. Hardened 420 stainless steel disc meets RC36 specifications. Semi-floating design yields a rotor with a higher resistance to wear, warping and rotor deformation. The scallop cut braking surface is drilled in a sweep pattern for optimal heat dissipation with a reduction in weight. Spoke Mount Rotors are designed for use with stock front wheels and calipers on H-D Touring models. Available as a stock replacement disc for front left and right applications.