Features: Using high-carbon steel, wear-resistant, wear-resistant, and long service life. 3/8" Extension Drill Bit Set Power Tool. Unique Design: the antidropping steel is better fixed: the automatic locking device is not easy to slip or fall off and cause dangerously situations. Greater bearing capacity. Usage: suitable for screwdriver handle or electric screwdriver tool (three-jaw chucks) to drive the sleeve. After installation, the joint can be converted into a square for head, which can be used for the installation of the sleeve. A powerful tool for conversion of Application: It can be used for installation on tool with shapes such as screwdriver, electric screwdriver, air drills, electric drills, and manual screwdriver. Specifications: Component: Metal Color: As Shown in the Picture Product Dimension: approx. 13.9x29x9.5mm/0.55x1.14x0.37inches Net Weight: 15g/0.03lbs 30g/0.07lbs Package Includes: 1PC/2PCS 3/8 Sleeve Extension Rod Accessories note: 1.Please allow 1-2cm errors due to manual measurement, make sure that you donot mind befores you order. 2.Due to the differences between different monitors, the picture may not reflect the actual color. Thanks for your understandings. Using high-carbon steel, wear-resistant, wear-resistant, and long service life. 3/8" Extension Drill Bit Set Power Tool. Unique Design: the antidropping steel is better fixed: the automatic locking device is not easy to slip or fall off and cause dangerously situations. Greater bearing capacity. Usage: suitable for screwdriver handle or electric screwdriver tool (three-jaw chucks) to drive the sleeve. After installation, the joint can be converted into a square for head, which can be used for the installation of the sleeve. A powerful tool for conversion of Application: It can be used for installation on tool with shapes such as screwdriver, electric screwdriver, air drills, electric drills, and manual screwdriver.