This is a stone-setting hair chisel for engraving. It is used to raise the prongs from all four sides after setting a stone. The tip angle is slightly obtuse compared to a regular engraving hair chisel. This is to prevent the raised prongs from cutting off at the edge of the metal. Please refer to the 5th illustration image. ★For the prong raising in the sample image, a 1.5mm tip width engraving hair chisel and a #12 mill chisel for making beads are used. The size of the prongs will vary depending on the engraver's strength, so the size of the applicable mill chisel will also vary. Please refer to the 4th image and the 5th illustration image. When rounding the prongs, use a mill chisel that is slightly larger than the prongs. If it's too small, the edge of the mill will stick out and look messy. ★To round the prongs and create beads, commercially available mill chisels and a chisel holder are required. You can use this as is, but the cutting edge will become dull and difficult to engrave with use. We hope that those with knowledge and skills in forming and polishing chisels will consider purchasing this. ★If you purchase multiple chisels currently on sale, the shipping cost will be reduced. Please specify the chisel number, etc., in the comment section before purchasing. We will relist them in a dedicated listing. (Example: Want to purchase two, No. 1 and No. 2) (Example: Want to purchase five-piece set and two No. 1 chisels)