Suitable for cleaning mild steel or aluminum & House decoration, construction, car repair, factory work. HEAT TREATMENT: For strength. Easy to start, cut or repair internal and external threads. PRECISION MILLED TAPS AND DIES: for cutting raw material or repair existing threads, remove screws and more function. Higher rigidity, better flexibility, longer lifespan. ADJUSTABLE TAP WRENCH: is convenient to fit different size taps use. Plug Taps are Suitable for cleaning & Re-Threading Mild Steel and Aluminum Materials. MADE FROM: durable steel material, long lifespan for use. Having been processed by anti-corrosive ways, the surface is stainless.