Feature: 1. The main part of the hole opener is made of hard alloy, which can effectively extend the service life and increase the work efficiency. 2. The cutting edge is sharp, the opening is neat, smooth, without broke edges, and the cutting resistance is small. 3. The front and rear inclined tooth‑shaped design has low resistance and strong perforation ability. 4. Wide range of applications and can be used to open holes in steel plate, iron plate, stainless steel, aluminum plate, calcium silicate plate, plastic plate, resin plate, FRP plate. 5. Professional manufacturing, superb craftsmanship and high accuracy help to provide the best performance. Specification: Item Type: Hole Saw Cutter Material: Hard Alloy Purpose: Can be used to open holes for steel plate, iron plate, stainless steel, aluminum plate, calcium silicate plate, plastic plate, resin plate, FRP plate. Plate Cutting Thickness: Approx. 3mm/0.1in Total Length: Approx. 88mm/3.5in Inner Wall Thickness: Approx. 20mm/0.8in Shank Diameter: Approx. 9.8mm/0.4in. Package List: 2 x Hole Saw Cutter2 x Spring2 x Hex Wrench Note: Not suitable for hand drills and impact drills, as well as ceramic tiles, concrete, walls, stone and other materials.