SIZE: Length 20mm (head not included) / Thread diameter M5 (5mm) ADVANTAGES: Hexagon socket head, can be easily installed with a hexagonal bit or a 4mm Allen / BTR key. This CHC screw is very widely used, it offers a high tightening torque as well as a head with a reduced footprint. DOES NOT RUST: Stainless steel A2 / 70 - V2A - AISI 201. Unlike zinc-plated or galvanized steel, this A2 stainless steel screw is corrosion-resistant and does not rust. This cylindrical screw is suitable for indoor and outdoor use, even in humid environments (except seawater).