The square bridge is one of the more interesting of all the package appearances, and it is also an easy one to identify. It is shaped like a small bench. The structure of the internal frame of the square bridge is tiled, and the four pins adopt double rows of parallel feet, so that all the shapes present a square shape. The structure of the square bridge is very stable, typical representatives are KBPC3 510, gbpc5010, etc., all commonly used in large industrial equipment, such as welding machine, elevator, motor and other equipment, is a hot sales.