These heavy-duty High Speed Steel Mortise Bits are made of high-quality HSS steel and do an excellent job at cutting the mortise. The bits come in different lengths (please see the picture below) and all have a 3/4" shank. Why You'll Love It These high-quality, heavy-duty HSS steel bits are designed for cutting mortise with a standard 3/4" shank.Unleash precision and efficiency with our heavy-duty Mortise Bits. Fabricated from top-grade hardened steel, these bits excel in creating accurate mortise cuts. Each bit is equipped with a standard 3/4" shank, ensuring compatibility with most drilling machines. These bits are available in a variety of lengths, offering you the flexibility to choose the right bit for your specific task. With these Mortise Bits, you can expect impeccable performance, every time. Features Material: High Speed Steel Hardness: 56HRC Clamping shank diameter: 3/4" (19mm) (Round) Bits are available separately or as a full set (includes 14 bits)