Bosch DG490CE 120-Volt Die Grinder Variable Speed High Torque Gear Box: Providing more power for the toughest applications Variable Speed: Set the perfect speed for each application Hardened -InchCollet: for longer life and increased precision Lock On/Off Slide Switch:Easily lock on tool for extended use applications Service Minder Carbon Brushes: Increased lifetime for less downtime with auto-cutoff when brushes need service