This product is a stone tool set, which is made of durable alloy and adamas material, with good texture, safe and practical. Easy to install and use, it can be easily applied to your work, a very practical accessory that will meet your needs well. Features -Color:Silver -Material:Adamas, alloy -Size:4.50X0.50X0.50cm/1.77X0.20X0.20in - The rotary file can apply in the mold processing manufacture, inverted round and trench processing. - Widely used in tool making, engineering, model engineering, wood , jewellery making, and sculpting. - Can be used on all types of metals, including stainless and hardened steel, as well as wood, jade, marble. - A great helper for your DIY woodworking, , engraving, and polishing. - Excellent craft, carefully down to every detail to give it and beautiful look. Package list: 20 x bits