Super Joint System (SJS) technology helps prevent motor and gear damage by allowing the drive shaft to slip if the wheel is forced to stop. Variable speed control dial enables user to match the speed to the application. Constant speed control automatically applies additional power to the motor to maintain speed under load. Soft start suppresses start-up reaction for smooth start-ups and longer gear life. Electronic current limiter helps protect the motor from overload. Labyrinth construction seals and protects the motor and bearings from dust and debris for longer tool life. Slide switch with lock-on setting for continuous use. 'Tool-less' wheel guard adjustment for easy adjustment. Wire cup brush: 3-1/2'. Spindle thread: 5/8' - 11 UNC. Overall length: 11-3/4'. Weight: 5.3 lb. Includes: lock nut wrench (782412-6), side handle (153489-2), lock nut (193465-4), inner flange (224378-9), 'tool-less' wheel guard (135107-4), 4-1/2' x 7/8' x1/4' 24 grit general purpose metal grinding wheel (741423-0-1).