Single/double cantilever beam units (wall-hinged beams)
Single double beams are also known as cantilever beam units or wall-hinged beams, or wall-hinged booms, and are standard appartus in a secondary school gymnasium or activity suite as well as military training gymnasia - they are a core element of army physical training equipment.
There are two types of beam - wall hinged, or travelling upright. The vast majority of installations are of the wall hinged type, but if you have a lack of wall space you can opt for at travelling upright version fixed underneath a roof beam or a piece of secondary steel.
The simple appearance hides a quite complex mechanism of counterbalance weights withing the uprights which enable the two beams, which are controlled by hauling lines, to be moved effortlessly into the desired positions. The beams can be used with their curved surface uppermost for gate vault type exercises or for linking to angled benches etc., or they can be rotated to use with their flat side uppermost for balance beam work.