Perfect Size: For precise drilling of various sizes from 5-35mm in diameter, one drill can handle various sized holes. High Quality Material: Titanium alloy liner is made of high quality HSS quality, which can ensure extremely high durability and reduce friction and heat. Titanium alloy drill bits are especially suitable for processing thin copper and aluminum workpieces / iron plates / wooden panels / plastic plates and other thin plate materials. Easy to drill: The position of the hole and the double flute design makes drilling faster and smoother, as well as precise drilling. Laser Cut: Dimensions are laser etched into the metal so they won't wear out even after repeated use. Applicable materials: plastic, wood, copper, iron, fiberglass, PVC, metal fin and aluminum3mm