Built to Last: This helicoil thread repair kit features drill bits and taps made from premium steel, heat-treated to HRC 55-62 for superior durability. The kit includes more metal thread inserts, each crafted from high-strength 304 stainless steel, ensuring longevity and reliability for all your repair needs. Complete SAE Kit: Ideal for restoring damaged threads, this SAE helicoil kit is perfect for engine repairs and other automotive applications. It comes with 131 pieces: 110 thread inserts, 5 twist drills (17/64', 21/64', 25/64', 29/64', 17/32'), 5 taps (1/4'-20, 5/16'-18, 3/8'-16, 7/16'-14, 1/2'-13), 5 breaking pin tools, 5 installation tools, and 1 hex key. SAE sizes cover most component specifications, making it suitable for your daily repair needs. Easy to Use: Designed for simplicity, this thread repair kit allows you to drill, tap, insert the coil, and break the tang to restore the threadquickly and efficiently