Material High Speed Steel (HSS) Type of surface treatment Titanium Hexagonal handle Surface recommendation Plastic, wood about this item Material- The bit set is made of high quality HSS, HRC 62-64 hard material, which has excellent hardness and wear resistance . The wood drill bit set offers optimum cutting force, high durability and high wear resistance. Perfect size holes for #5, #6, #8, #10 or #12 screws. Standard 82 Angle- These countersink bits for pilot end screws are designed to match to the most commonly used 82 wood screws on the market. 1/4'' Hex Shank - The quick-change chuck is suitable for hammer drills and other power tools. It perfectly meets all your daily needs. The product interface size is suitable for most household electric drills. Simple and easy woodworking kit. MULTI-PURPOSE- Suitable for home or professional woodworking, suitable for wood, plastic, PVC, fiberboard, panel particleboard, plywood, rubber and more. Drilling, countersinking and countersinking in one step. This item comes with 5 spare bits. Product Description countersunk head drill bit set, countersunk head drill bit, drill bit set, countersunk head drill bit, drill bit< /p> Counterbore Counterbore Kit, 5 Pack, Quick Change Adjustable 1/4" Hex Shank Made of high quality high speed steel (HSS) for a long service life. Ability to drill pilot holes or pilot holes and screw in countersunk or countersunk head connectors in one step. The pliers quick change and precision machined are compatible with hammer drills and other power tools designed to accept 1/4" hex shanks. Standard 82 thread L he 82 countersink angle matches the head angle of most screws you are likely to encounter. This set of bits allows all surfaces of the screw head to contact the wood simultaneously with equal force. No need to apply too much force on the screw to force the knife. double life 5 freely replaceable cutting heads with adjustable depth and detachable for easy cleaning and replacement . Worn or dull knives can be easily replaced. L button. hex head screw 5 #1.98mm 6 #2.38mm 8#2.78mm 10#3.175mm 12#3.56mm