Ultra Cutter 1-3/8" (35 MM) Actual Hole Size. Lasts 10 Times Longer Thanstandard Hole Saws. Precision-Ground Teeth Cut Smooth, Burr-Free Holes With Ease. 1/4" (6.35 MM) Capacity. Durability and Speed Provide Low Cost Per Hole. Split-Point Pilot Drill Prevents Walking - Makes Accurate Hole Placement Easy. Spring-Loaded Slug Ejector Saves Time. No Tool Required to Change Cutter Sizes. Less Chance Of Broken Teeth Because The Saw Body Is Machined Out Of Solid, High-Speed Steel.