Feature: Made of high precision tungsten steel which has high hardness and wear resistance. With good milling performance, it ensures a high working efficiency. As specially treated, their surface is clean, neat and without defects. Includes 10 different sizes of cutters to meet your different needs --- 0.8/1.0/ 1.2/1.4/1.6/1.8/2.0/2.4/3.0/3.175mm.Has high strength and great bending resistance, not easy to break. Widely used when carving, cutting, engraving, milling, routing, etc. and can be used on PCB, hardwood, acrylic, etc. Comes with a plastic box to prevent them from oxidizing, and also convenient to collect. Specification: Blade diameter: 0.8/1.0/1.2/1.4/1.6/1.8/2.0/2.4/3.0/3.175mm Shank Diameter: 1/8''/3.175 mm Blade length: 13 mm Total length: 38mm