Make of Black Carbon Steel, which is wear resistant, and with high hardness Suitable for gypsum board, woodworking board, dry wall and more collar design limits the penetration of screws to the board and prevents damage to wall or boards by twisting screws overly Suitable for most electric screwdrivers, manual screwdrivers, electric drills, hand drills, for easy screw installation and removal These bits help you fix the screw exactly in place without worrying about wobbling or misdirection The and nonslip design allows the screw to attach to the bit without falling off, making your work easier and effortless, Manufacturer: RGYBAO