General description This HSS woodworking twist drill bit set includes a mortise drill, square drill bits, and mortising chisels designed for creating square holes in wood. Made from high-speed steel, these tools are durable and resistant to wear, ensuring a long service life. Technical specifications Material: High-speed steel Sizes available: 6.4mm, 8mm, 9.5mm, 12.7mm Usage The square drill bits are designed for use in various positions, making woodworking tasks more convenient. Note that these bits cannot be used directly with an electric drill; they must be positioned on the mortise to extend the operating time of the drill. Other information Package includes: 1 x square drill Color: as pictures show