Nortools Alloy Steels Tap And Die Set,Sae Inch Sizes Essential Threading Home ALLOY TOOL STEEL Imported ?PREMIUM MATERIAL AND DURABILITY: Industrial grade GCr15 bearing steel construction ensures durability and tool longevity ?EXCELLENT CUTTING PERFORMANCE: All cutting teeth are precisely CNC machined and accurately heat treated to Rockwell hardness 60 HRC for best threading performance ?TAPERED TEETH DESIGN: Tapered coarse and fine taps and dies start threading more easily and smoothly, and prevent over threading ?ALL-INCLUDED SET: This kit comes with a full range of most popular SAE taps dies with both coarse and fine sizes, plus all needed wrenches, handles, a gauge and a storage case ?VERSATILITY AND WIDE APPLICATION: Perfect to create new threads or repair damaged threads on plastic, aluminium... a good tool for home, backyard, garage mechanic...also can use them on small engines like: snow blowers, lawn mowers and outboard motors...Our big recommendation is that before you use any tap or die in this set, is to buy a small can of 3-in-one oil for use as a thread cutting oil