1、CLEAN PRODUCTION: Countersunk drill bit can create perfect countersunk holes for flat head screws and plug head screws, without the need to split wood, and enjoy clean engineering with a drill bit set. 2、ADJUSTABLE: Countersunk drill bit can be adjusted for screws of different lengths and create countersunk holes on the wood to ensure consistent depth of the countersunk holes, while protecting the working surface and preventing clogging of debris cavities. 3、WIDE USE: Suitable for wood, medium density fiberboard, particle board, dense plywood; Please avoid cutting black metal and other materials such as steel, iron, sand, etc. 4、CEMENTED CARBIDE MATERIAL: Countersunk drill bit set is made of cemented carbide material, has a hardness of HRC 50 to 54, provides excellent cutting ability, strong durability, and good wear resistance. 5、4PCS: There are 4 pieces countersunk drill bits in the package 1/4 x 5, 1/4 x 8, 1/4 x 3, D1/2 x Use them to make your your work better!