The Astro Pneumatic 17263 Solid Carbide Spot Welding Bit - 3 Flutes - 10mm removes spot welds in Boron and other materials. 10mm drill bit especially designed for spot weld drilling. Made of ultra-hard Solid Tungsten Carbide which prevents bit dulling from overheating. 3 flute design provides extra cutting surface which make cutting faster. Fast and easy way to remove most common size of spot welds in auto restoration and body repair work. Bit has center nib to prevent walking.