Features Specification Features: Made of high speed steel with durability and wear-resistance, which can be used for a long time. Ideal for woodworking to quick disconnect adapters, such as wood window or door knockers, etc. 8 kinds of sizes are available to meet your daily working needs. The automatic positioning center design increases positioning accuracy and efficiency. 17 pieces of luxury package includes 16pcs self centering drill bits and 1pc hex key. Specifications: Material: High Speed Steel Color: Silver Package Size: 13 * 10 * 2cm / 5.1 * 3.9 * 0.8in Package Weight: 315g / 11.1oz Package List: 16 * Self Centering Drill Bits 1 * Hex Key Package List 16 * Self Centering Drill Bits 1 * Hex Key