The set contains 2 keyless drill chucks and 10 drill bits in the range of 1.0-4.0 mm. One silver lining measures 2.7 inches with a clamping range of 0.3-6.5 mm, and the other black measures 1.9 inches with a clamping range of 0.3-3.6 mm. These sizes are designed to meet a wide range of work requirements. The drill chuck extension is small size, and light weight, which will not bring extra burden to your operation. These keyless drill chucks can easily turn a cordless electric screwdriver into a drill or grinder; You need to turn the tail to make adjustments to quickly switch tasks and maintain work progress; They are essential power tool accessories. Featuring a 1/4 inch hex shank, keyless drill chuck bit seamlessly fit into power tools for quick and secure installation. With this quick-replacement capability, you can easily convert your cordless power screwdriver into a drill, enabling seamless transitions between different tasks and reducing project completion time. Made of aluminum alloy material with body, and removable steel connecting rods to withstand rigorous use and provide long-lasting performance. Tough materials reliability and durability so you can tackle a variety of drilling tasks with confidence. With their different specifications, these drill chucks are compatible with most drills and cordless screwdrivers. The two different keyless chucks are suitable for a wide range of applications, including daily maintenance, car repairs, working in garages and warehouses, as well as office and home use. Product Name:2Pcs Drill Chuck with 10pcs Drill Bit Set Easily lock and release the drill for fast conversion: change the hex shank driver to a drill; hex drive power tools can be used with drills. Colour: Material:Metal Package Contents: 1set * drill propeller Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.