Hole saw, Electron beam welded, M-2 high speed steel, Cutting edge Rc 63-65, varied tooth design, Spring steel back, positive rake tooth, Bi-metal means high speed steel teeth welded to a "spring" steel back, Last 5 time longer, Made in USA, 1-, 50" cutting depth, Length: 3, 25, Width: 2, Height: 2 SKU: JNSN24630