Flexible Electric Drill Bits Extension Spring Rod Soft Shaft Screwdriver Extender Rotating Wrench Tool Accessory Feature: 1.360 rotation at will, suitable for narrow spaces with various angles. 2. It can be used with ratchet wrench, square interface wrench or electric drill. 3. Four-way interface, matched with anti-jam ball. 4. Spring technology, which can be used flexibly and has stronger support. Specification:  Type Interface Diameter Interface Clamp Slot Diameter Total Length Large      1/2in          1/2in           21          245 Medium    3/8in         3/8in           16          197 Small      1/4in          1/4in            11          145 Material: metal Note: Due to the different monitor and light effect, the actual color of the item might be slightly different from the color showed on the pictures. Thank you! Please allow 1-2cm measuring deviation due to manual measurement.