General description Heavy duty steel tips make this 4Pcs Hex Nut Drivers Screw Driver Tools Kit Set ideal for disassembling RC helicopters, airplanes, cars, and boats, particularly 450 Helicopters/CP V2. Enjoy the ultimate first-person view experience with these durable tools. Technical specifications Material: Steel Total length: 17.5 cm / 6.9 inch Sizes included: 4.0mm, 5.5mm, 7.0mm, 8.0mm Package Contents 1 x 4.0mm Hex key Socket Screw Driver 1 x 5.5mm Hex key Socket Screw Driver 1 x 7.0mm Hex key Socket Screw Driver 1 x 8.0mm Hex key Socket Screw Driver Other information Note: Light and different displays may cause the color of the item in the picture to differ slightly from the real thing. The measurement allowed error is +/- 1-3cm.