Diameter: 3-1/2"Shank: 3/8"Drill Fast, Accurate Holes Through Materials Up To 1" DepthCuts Cast Iron, Steel, Stainless Steel, Aluminum/Pipe And FRP/PVCUltra-Sharp, Triple-Edge Tungsten Carbide Teeth Cut Quick, Smooth, Perfectly Round HolesFlattened Shank For Use In Power Drills And Drill PressesSafety Collar Stop Prevents Over-Penetration For Safer OperationSpring Loaded Pilot Drill Ejects Metal Plug Quickly For Increased ProductivitySignificantly Outperforms Bi-Metal Hole SawsPerfect Portable Tool For The Professional Contractor, Electrician, Plumber And HVAC/Sheet Metal TradesmanFollow Speed Recommendation Chart Based On Material And Diameter For Best Results