CR-V steel socket (chrome vanadium steel alloy), 40 # steel handle, built to last. Universal plug from 7 mm to 19 mm. Fits standard 1/4 to 3/4 " and metric 7-19 mm nuts and bolt heads. Unique design that automatically adjusts to any size or shape, compact and easy to carry. Perfect for automotive industry, home maintenance, manufacturing, construction and other industries, also loved by home decor enthusiasts. Package content: 1 sleeve + 1 key + 1 link Features: This is a universal socket that instantly adjusts to the grip of hex nuts, screw eyes, hooks, offset screws and bolt heads. Fits standard 7-19mm nuts and bolt heads. 1/4 " to 3/8 ". Drive adapter (7mm to 19mm) 6-point universal socket for standard and metric nuts and bolts. Use with nuts, hex nuts, square nuts, eye screws, cutting hooks and offset screws. Drill adapter that turns the electric drill into a power outlet Self-adjusting to fit thousands of bindings Eliminates rusty and damaged fasteners. Specifications Range of use: 7-19 mm. Content: 1 set of 3 universal electric drill wrenches 7-19 mm