Features [30 Piece Set] This twist drill bit set includes 29 twist drill bits ranging from 1/16in to 1/2in, with standard 1/4in shank, along with one adapter. [Convenient Storage] These twist drill bits are come with a sturdy storage box, allowing for easy organization and portability. [High Speed Steel] The drill bits are made from high speed steel, ensuring high hardness and long lasting durability. [Versatile Compatibility] Suitable for drilling through various materials such as steel, cast iron, other metals, as well as plastics and wood. [Reliable Performance] The high speed steel drill bits provide reliable performance and durability for precise and efficient drilling. Specification: Item Type: Twist Drill Bit Material: High Speed Steel Specifications: 1/16in, 5/64in, 3/32in, 7/64in, 1/8in, 9/64in, 5/32in, 11/64in, 3/16in, 13/64in, 7/32in, 15/64in, 1/4in, 17/64in, 9/32in, 19/64in, 5/16in, 21/64in, 11/32in, 23/64in, 3/8in, 25/64in, 13/32in, 27/64in, 7/16in, 29/64in, 15/32in, 31/64in, 1/2in Shank: 1/4in Hex Shank Package List:29 x Twist Drill Bit1 x Extension Rod1 x Storage Box Package List 29 x Twist Drill Bit 1 x Extension Rod 1 x Storage Box