PROFESSIONAL HOLE SAW DESIGN: Features improved durability, clean performance and easier plug removal in multiple materials ENHANCED M42 ALLOY: Contains 8% cobalt alloy to withstand high-temperature applications and deliver 20% more life, and it is stronger for cleaner cuts TRIANGLE SLOT DESIGN: Improves efficiency of plug removal and reduces heat due to triangle shark tooth shape PROGRESSOR TOOTH DESIGN: Hole saws feature alternating teeth size for performance, cutting faster and lasting longer in wood, metal and plastic materials REINFORCED SHOULDERS: Provide added strength and longer life to the hole saws DEEPER CUP: Can drill through thicker materials, for more applications in such materials as wood, drywall, metal and plastic VERSATILE: Works with standard arbors and is ideal to pair with a spinlock universal arbor (sold separately)