Tonsiki 3 Pieces 1/4" 3/8" 1/2" Hex Shank Square Nut Driver Power Drill Bit Extension Socket Adapter Set with Color Coded Ring General Usage: This 3 piece Hex Shank Bit Driver Extension Bar Set is designed to meet a variety of needs. Fits snugly and securely in your drill chuck or hand held driver. Consisting of your most common bit sizes 1/4", 3/8", and 1/2" changing shank sizes.Provides versatility and convenience no matter which tool you chose to use. Great for the DIY, household maintenance, and most general repairs, not for industrial work. A great tool addition to any tool box set. Material: High-carbon steel,to avoid broken when you using this set. Easy to Choose: Different colour coded rings, make it easy to pick the right one. Purpose: This adapter set is designed to provide a securely locked in extension to your existing tool. Provides additional length to reach into a multitude of hard to reach spaces. The spring ball lock ensures a tight fit into the driver head to prevent slipping during use. Specifically machined to fit securely into a hand held driver, drill driver or impact wrench. Multifunction: used in the installation of pneumatic screwdriver, electric screwdriver, pneumatic drill, manual screwdriver and other installation for the hexagonal tool .It is a good accessory for conversion.