Features: *Make drilling, countersinking and couterboring a step process. *1/4" hex shank can be used with power drills and quick change chucks. *The adjustable stop collar allows you to either set the screw head flush with the surface or drill. *Countersinks will drill the pilot hole and countersink or counter-bore for screws in step. Countersink to drive the head of the screw flush with or slightly below the surface. Specifications: Product name: Countersink Drill Bit Material: Steel, Alloy Steel Color: Grey, Orange(As shown) Optional Size: 2.88, 38, 3.28, 3.58, 2.810, 310, 3.210, 3.510 Shank: 6.35mm(1/4" ) Hex Suitable for: Woodworking drilling, counterbore. Quantity: 1pc Package Included: 1 Drill Bit Note: 1.Transition: 1cm=10mm=0.39inch. 2. The real color of the item may be slightly different from the pictures shown on website caused by many factors such as brightness of your monitor and light brightness. 3. Please allow slight manual measurement deviation for the data.