Features: Push Drive Technology - minimizes power consumption under no load. Motor speeds up to full rpm when screw is inserted into a board. Lock-on button for continuous screw driving. Compact and ergonomic design for screwdriving. One touch locator allows for easy locator installation / removal with single action.  Specifications:Capacity: Drywall screw: 4mm. Driving shank (Hex): 6.35mm. No load speed (rpm): 0-4000