This Milwaukee® small arbor with cobalt pilot bit, is designed to optimise the performance of the HOLE DOZER™ with Carbide Teeth hole saw. The cobalt pilot bit provides 10X longer life than standard HSS pilot bits, matching the performance of the HOLE DOZER™ with Carbide Teeth hole saws when drilling through the toughest materials like stainless steel, cast iron, wood with nails, thick metal & abrasives. The pilot bit's 135° split point tip engages on first contact and the quad edge tip decreases heat build up helping you cut faster.