The Makita 4-1/2 in. SJS II High Power Angle Grinder (GA4542C) combines power, convenience, comfort and motor-protection features for longer-lasting industrial performance. The GA4542C is equipped with SJS II, a mechanical gear drive system to help prevent motor and gear damage by dampening the force on the gear when the wheel is forced to stop. SJS II also features a leaf spring and cam gear drive mechanism that is engineered to reduce vibration for increased operator comfort during extended use.

The 12 amp motor delivers 2,800-11, 000 RPM for versatility and maximum productivity. Labyrinth construction protects the motor with a complex set of channels, prohibiting dust and contamination from entering the motor. A zig-zag epoxy applied to both sides of the armature coil, and a powder-coating to the field. This forms a barrier under rotation and is engineered to protect from dust and debris penetration for longer tool life.