niceeshop(TM) Hex Screw Driver Screwdriver Tools Kit Set for RC Helicopter (Black,4Pcs) Material:metal+plastic 1.5MM 2.0MM 2.5MM 3.0MM Hex Screw include Diameter of handle:18mm; Total length: 195mm; Length of handle: 90mm Used for disassamble hex screw in helicoptor and other place