Black/Speckled, General Purpose, Long Life Flywheel Grinding Wheel. Flared cup, 6"/4-1/2" x 2-5/8", 1-1/4" Arbor Hole. Silver Seal offers the best wheel for each application. When selecting a wheel, keep in mind that harder flywheels need a softer stone and softer flywheels need a harder stone. W...