This drill bit designed for wood boring projects. It features high grade durable construction. IRWIN 3-pack tri-flute bit set includes 5/8-in Speedbor Max, 3/4-in Speedbor Max and 1-in Speedbor Max, perfect for wood drilling applications Tri-Flute design for faster chip ejection Cutting spurs have 3 cutting edges for added durability Screw tip allows bit to self-feed for ease of use Grooved hex shank prevents slipping in drill chuck or bit extension Fits all standard 1/4 In. quick change chucks