Please read the product size carefully before buying to make sure that you are not buying wrong. Specification Example:M3x6mm(40Pcs) = thread diameter 3mm x screw length 6mm , 40 Piece for a set. Thread Diameter: 6mm/0.23 inch Rust-proof, corrosion-resistant, high hardness. Various uses Suitable for a variety of fixed applications. Small repairs such as door handles or garages around the home, garages, faucets, knobs, gunsmithing, weapon repair, plumbers, etc.