Used for fastening to a bolt when mechanically joining materials together and preventing loosening from vibration or back off. The hexagonal shape provides increased leverage for use with a wrench during installation and disassembly. Premium SUS304 stainless steel ultimate rust and weather resistance. Specification:Material: SUS304 Stainless SteelSurface Treatment: VibrationThreaded: G1/2"Hex Width: 24mm / 0.94"Height: 4mm / 0.16" Package Content:1 x Pipe Fitting Hex Locknut