The set contains 2 keyless drill chucks and 20 drill bits in 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 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 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 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. The drill chuck for impact driver is 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. Color:As Shown Material:Metal Package Contents: 1set * drill chuck adapter Only above package content, other products are not included. Note: Light reflection and different displays may cause color of item in picture a little different from real thing. The measurement allowed error is +/- 1-3cm.