Irwin Spiral-Flute Extractor, 6-Piece Set, EX-1 to EX-6: * Aggressive left-hand spiral tears into fastener materials while enhancing extractor grip * Torque-enhancing tapered flute embeds itself more easily with each turn * Clear, permanent extractor size and recommended drill bit stamps simplify tool selection * When used in conjunction with an appropriate drill bit (sold separately), spiral-flute, high-carbon-steel extractor makes removing broken studs, bolts, socket screws and fittings easy * Head Type: Spiral-Flute * Material(s): High-Carbon Steel