... :PCB board,Fiberboard,carbon plate,MDF,Acrylic Radius Bottom Engraving Bits Material: Tungsten solidOverall Length: 40-80mmModel Number: tw-000832Coating: NOTHING ... ° , 60 ° , 90 ° , can be non-standard customization. Processing features: Font carving, v-groove, three-dimensional clearance angle, chamfer, v-type three ... title keyword: Flat knife, chisel, knife engraving. Radius Bottom Engraving Bits