Features: brand new and high quality Extremely for sharp three-sided arc surface flute type may discharge chips from the hole on all sides quickly and leave a smooth finish surface without harming the wood. Made of high quality stainless steel material, practical and durable. Mainly applied for woodcarving and detail on bird , fish scales, and more crafts, such as craft deep grooves, v-slots, curve patterns & lines, get a nice and smooth finished craft effect. Professional engraving, amateur, students can use. For wood carving, these are excellent tools. You will get 5 pieces engraving bits. You can use it according to your needs. Specifications: Material: Stainless Steel Shank Diameter: 4mm Package Includes: 5x/Set Engraving Drill Bits note: 1.Please allow 1-3cm errors due to manual measurement, make sure that you do not mind before you order. 2.Due to the difference between different monitors, the picture may not reflect the actual color of the item.