zvd step drill bit, 4pcs hss metal countersink drill bit 4 12 20 32mm step drill bit steel countersink tapered triangle drill bit

3 1size 1 72mm the scale on the drill bit is 4 12. 1 72mm 4 20. 1 102mm 4 32. 1 72mm twist drill bit. the drill can handle holes of different sizes hss sturdy and rustproof made of high quality hss, it cuts through thin materials quickly. hss provides extreme durability, and the drill bits are rust