ZENY 800W Drywall Sander Electric Adjustable Variable Speed Dry Wall Sanding NEW NoteStart Or ON/ OFF button not light up, pls press button firmly to ensure it's in correct postion. Still not light up, open the case to see if interior wire loosen or fallen off. Any questions or concerns, feel free to contact seller for solution. Heavy duty construction and Sturdy & Durable Variable Speed Control - 6 Positions Between 1,000 to 2,000rpm 6 Sander Discs included, sanding pad diameter 8.8 inches Light-weight, easy to reach almost any corner and angle