Top quality: Made of high quality carbide alloy with anti-kickback. Heat resistant tflon coating and construction, which makes it not only strong and durable, but also excellent in anti-rust function. Safety instructions: 8mm universal shank bits provide more stability and less vibration when in use.When installing on the electric drill, try to tighten the shank of the tongue and groove router bit at the bottom, otherwise it will be easy to bend the rod. Widely Application: This tongue and groove router bit set is truly versatile for your added convenience. Perfect for wood, MDF, chipboard, compact plywood board. Note: Do not cut ferrous metals and non-wood materials, such as: steel, iron, sand, etc. Professional woodworking tool kit: This tool kit includes 2 tongue and groove router bits, perfect for woodworking, edging, cutting, grooving, grain wood projects. Satisfaction: ASNOMY aims to provide high quality products and customer service to all of its customers. Any issues, just contact us and our after-sales team will resolve your issues ASAP.