the appearance of steel doors on the market is very similar to security doors, in terms of anti-theft performance, standard security doors with thick steel plates, strong impact resistance, the implementation of the national mandatory standards; and steel doors are implemented by each enterprise's own corporate standards, steel doors are widely used in the interior and exterior of various buildings. Steel doors for outdoor use are normally used for a variety of purposes, requiring galvanized steel sheets, each reinforcing member using oxygen protection welding to weld reinforcement, the addition of waterproof thresholds (or bottom seal), anti-theft pins, UV-resistant high-quality coating to adapt to the harsh working environment of outdoor sun and rain.