ENGINEERED FOR HEAVY-DUTY TAPPING - stop worrying about broken tools in critical projects. Our taps are forged from premium High-Speed Steel (HSS) with full nitriding treatment, offering exceptional hardness, wear resistance, and toughness. Specifically designed to easily cut through thick, hard materials like engine blocks, hydraulic systems, and machine tool bases without snapping; 3-PIECE PROGRESSIVE TAPS FOR BLIND HOLES - achieve flawless, burr-free threads with our specialized 3-tap sequence per size. Each tap features a varying major diameter and chamfer, progressively reducing cutting load. The final tap features a complete thread profile with a flat tip, making it the perfect solution for bottoming out blind holes in high-precision mold machining; PRECISION DIES & SMOOTH OPERATION - the threading dies are crafted from high-grade GCr15 alloy steel for superior longevity and sharp cutting edges. Combined with the ultra-smooth surface finish of our nitrided taps, this set minimizes friction, prevents jamming, and ensures a clean, highly precise thread profile every time you repair or create internal/external threads; COMPREHENSIVE METRIC RANGE (M12 & BELOW) - tailored for professional mechanics, mold makers, and marine technicians, this set includes the most highly utilized metric sizes up to M12. Whether you are dealing with small-batch precision parts manufacturing or reinforcing high-hardness mold thread holes, you will have the exact size required for the task at hand; RELIABLE ACCESSORIES FOR FIRM CLAMPING - a high-quality tapping job requires a solid grip. Our set includes an industrial-grade, heavy-duty tap wrench that firmly secures the taps, preventing slippage during high-torque manual operations. Built to withstand the rigorous demands of daily use in auto repair shops, factories, and machining workshops. toolant Professional Tap and Die Set, HSS Nitrided Taps with 3-Piece Progressive Design for Blind Holes, Heavy-Duty Metric Threading Tool Kit for Mechanics, Engine Block & Mold Repair