DescriptionMade of premium YG9X alloy which features high hardness and strong abrasion, the hole cutter is widely used for metal tapping, like aluminium alloy, stainless steel board thinner than 3mm and iron board thinner than 10mm. Perfect and practical tool for metal hole cut.Features- Color: Gold. - Material: Metal. - Package Size: Approx. 10 x 13 x 4 cm / 3.9 x 5.1 x 1.6 inch. - NOTE: These cutters only work with electric drills. - Made of premium YG9X alloy, the hole cutters are of high hardness and strong abrasion. - Package include 5pcs hole cutters in size 16mm, 18mm, 20mm, 25mm and 30mm. - can easily cut metal out. Very useful and helpful. - Applicable for various metal plates inclued steel, aluminium alloy, etc.