Spyder's carbide tipped Tarantula cuts the toughest materials - steel, stainless steel, nail-embedded wood, fiber cement board, and more. Durable tungsten carbide cutting teeth make up to 50x more cuts than conventional bi-metal hole saws, and they are up to 10x faster. Use Spyder's Rapid Core Eject arbor system to remove cores without prying - drill hole, press button, pull back the hole saw, and eject the core. Cut at an angle, and use two adapters (second adapter sold separately) on one pilot bit to enlarge existing holes. All Spyder hole saws fit on Spyder Rapid Core Eject arbor/pilot bits, and on universal hole saw arbors.