New from Southco is a concealed hinge that comes in three versions: 180o
free-swing, 90o free-swing and door-stay styles, in stainless steel or
zinc-plated steel. The hinges work by rotating about a virtual pivot
point, which allows the door to open to a full 180o with no gap between
door and frame. They are completely concealed, providing a clean outer
panel and eliminating attack points for vandals.