<p>High Quality: Compared with ordinary drill bits, our drill bits are treated with titanium plating, which is harder and more durable. Each cutter is constructed from heat-treated steel for long-lasting, repeatable performance with easily replaceable bits. Uniquely designed steel countersink pilot hole to allow proper size socket to be installed on the screw head, secured with hex key for easy replacement and adjustment.Quick change: adjustable counter sleeve depth, drilling and countersink for wood screws without changing drill bits. The drilling length can be adjusted for different screw lengths simply by loosening and tightening the grub screw. Widely used: perfect for plastic, wood and metal, perfect for home DIY and general building use /engineering. At the same time, Christmas gift for dad/father, husband, boyfriend, man, handyman.</p> <p>Note: The data are all manual measurement, please allow 1 - 3cm error , due to the difference in light and display, there will be a certain color difference, depending on the physical object received.</p>