【Materials】The twist drill bits are made of high-speed steel for high hardness and durability. Using high-speed steel drill bit materials to improve machining efficiency and convenience. 【Size】This set contains 8 drill bits of different sizes and the most popular drill bits, including 4mm, 4.2mm, 4.5mm, 5mm, 5.2mm, 6mm, 8mm, 10mm drill bits. 【Design】The extra-long cutting edge allows you to drill deep holes with these drill bits. The sharp head design provides a center point, high maneuverability, faster with less effort. 【Usage】They are ideal for drilling most materials and soft materials. Suitable for most drilling jobs and materials such as thin metal, aluminum, iron, carbon steel, wood, plastics, etc. 【Advantage】Sharp twist drill bits make drilling easier and more effortless. Incisive twist drill bits will make drilling easier and easier. The long cutting edge allows you to use these drill bits to drill deep holes. Product Features: The twist drill bits are made of high-speed