Hitachi 725797 Spline Shank Adapter to 3-Jaws Drill Chuck 1/2-InchThread for Hitachi Spline Rotary Hammers 1/2-Inch 20-thread spline shank Used with spline rotary hammers Adapter for 3-jaw drill chuck Quick change design Comes with a 30-day limited warranty Quick Change No Energy Loss No Weak Points