Fits all common chucks 3/8" shank - not meant to turn by hand Shank will only turn when attached to drill 2 built in holes that are designed to fit fence clamps to secure the square to your piece Built in mounting holes to safely secure the DrillPump to a flat surface for proper usage The DrillPump750 is designed to work with most electrical drills with a maximum speed of 2, 800 RPM. This pump is ideal for draining small ponds, fish tanks, small pools or even a flooded basement. The hose connection is 3/4” and uses any standard garden hose. The unit pumps up to 750 gallons per hour and is self-priming up to 12 feet. The 3/8” shank on this unit fits all common chucks for most drills. It is recommended to use silicone grease. To apply, unscrew the side and put a bit of grease on the housing where the rubber fan blades touch, then reassemble. When using, the drill should be set to run forward, turning the pump in a clockwise direction.