Soft start reduces movement of the tool on startup increasing user control High effeciency motor design improves performance in demanding applications No-volt release switch prevents the unit from starting unitentionally when locked on Dust ejection system removes majority of debris from the air which passes over the motor Low profile gear case allows access in confined areas Anti vibration side handle to improve user comfort Anti lock flange prevents flanges from permanently locking up and locking the disc on Pop off brushes protect the armature from damage at the end of brush life