The powerful SENCO DS425AC is designed for high-volume, high-speed screw applications. Professional remodelers, contractors and DlYers will appreciate the convenience of the 3300 rpm collated screw system, which increases productivity by eliminating the need for handling loose screws. The DS425AC has corded power to drive 11/4" - 3" screws into even the toughest work surfaces. With the built-in extension you can adjust tool to the proper height to speed productivity and save your back and knees. Sometimes called a stand up sub floor screw gun or subfloor screwgun.