【Hole Saw Kits】- There are 15 sizes of hole saws for you to choose. You can cut holes from 15mm/0.59in to 3mm/2.1in according to your needs. 【Resistance and Durable】- The hole saw kit is made of HSS high-speed steel. The saw blade is extremely sharp, low consumption, durable, impact resistance and wear resistance. 【High Hardness】- The saw blade is quenched and has high hardness and strength(hardness 59-60HRC). Hole saw kits can drill about 7/9” depth for the wood, and 1/5” for the stainless steel. 【Wide Range of Applications】-The carbide teeth of the hole saw kit is able to cut clean, round holes in stainless steel, mild steel, iron, aluminum plate, alloy plate, plastic sheet, copper and brass.Product Description Features: 1. Cutting holes from 15mm/0.59in to 3mm/2.1in 2. Made of HSS high-speed steel, extremely sharp, durable, impact resistance and wear resistance. 3. Hardness 59-60HRC, drill about 7/9” depth for the wood, and 1/5” for the stainless steel. 4. Each HSS hole saw is individually packaged in a plastic box. 5.