PRODUCT SIZE: You will get 2 pieces keyless drill chucks, one silver with a length of 2.7 inches for clamping range: 0.3-6.5 mm, and a black one with a length of 1.97 inches for clamping range: 0.3-3.6 mm. Two sizes of keyless drill chucks can meet most of your work needs. MATERIAL: The drill conversion chuck set is made of aluminum alloy and carbon steel, rust-proof, wear-resistant and durable, and has a long service life. UNIVERSAL 1/4 INCH HEX SHANK: The drill adapter's universal 1/4 inch hexagon handle can be easily inserted into an electric screwdriver, which is easy to use and quick to switch. EASY INSTALLATION: This keyless drill chuck converter can easily turn an electric screwdriver into a drill or a grinder.It can be installed and working in a few seconds, without additional installation tools. It is small and portable, improve your work efficiency. WIDE RANGE OF APPLICATION:These drill chucks have various specifications and can be adapted to most drills and cordless power screwdrivers.Two keyless drill chucks of different sizes can be used in daily maintenance, auto repair, garage, warehouse, office, home, etc.