DEN DF 1690 Boron BitThe Boron Killer. The ONLY way to drill through Boron Steel is with this bit. This drill bit was created to specifically cut spot welds from Boron Steel. Made of Tungsten Carbide this 8. 0 mm, special multi layered coated, 3 fluted drill bit is the only bit that is tough enough to drill through and survive Ultra High Strength Steel, aka Boron Steel. The three cutting edges help spread cutting forces over a greater area, thus helping prevent premature