About this item Product: 2 pc 5/8"-11 Male to 3/8" Hex Handle Diamond Core Drill Bit Adapter Usage：Will this Connect Core Bits with 5/8"-11 Threaded Female Arbor, Make it Changes to Connector to 3/8" Hexagonal Shank for Electric Drill. Quality：Made of Strong Hardness Alloy Steel Metal, Heat Treatment, High Strength, Surface Nickel Plating,Twist Resistant Alloy to Ensure Long Service Life. Function:Combine with a Grinding,Cutting and Polishing Tool with a Standard Collet Handle,Combined with the Core Drill Adapter,use your Diamond Finishing Drill Bit / Grinding Machine for Granite,Concrete,Glass,Brick,Etc. Meet your Various Work Needs. Widely Use: Twist Resistant - Most Diamond Core Masonry Bits, Tile Drill Bits, Stone Polishing kit, Granite Polishing Kit, Diamond Polishing Pads, Diamond Cup Grinding Wheel, Grinding Stone for Drill and Back Holders are 5/8 inch - 11 Threaded.