This is a pro-grade jewelry tool for setting stones! It's a 3mm Hart Bur with a 90-degree angle, perfect for cutting seats for round stones in prong settings. Made by FOX in Germany from super-hard vanadium steel, so it stays sharp through a lot of use. The color is gray, MPN is 156 030. It's brand new in its packaging. If you're into making rings, pendants, or any prong-set jewelry, this bur is a must-have in your toolkit. It gives you clean, precise cuts every time. Also great for general jewelry making and repairs. UPC: 806149981985. Whether you're a hobbyist or a pro jeweler, having the right bur makes all the difference. This is the right one for prong work.