With the International Tools 29.300 Eco screw extractor set, you safely remove broken bolts, sheared studs, and damaged screws without ruining surrounding internal threads. This 5-piece set covers sizes NR.1 through NR.5 for standard metric threads from M3 to M18. Simply drill a pilot hole into the center of the broken fastener, and the tapered reverse spiral profile bites firmly into the material as you turn counterclockwise. This allows you to back out seized or snapped fasteners smoothly and with full control, eliminating the need to drill out and re-tap the hole completely. Ideal for automotive repairs, machinery maintenance, and metal fabrication.