Back mounting stage cylinders is a technique used when diving on rebreathers or in cave systems were the diver has limited areas. Side mounting uses twin independent cylinders and regulators, each attached to the diver’s body at the hip and shoulder via a Bungee strap. The cylinders then lie along both sides of the diver (hence the name "side mount") with the valves under the arms and cylinders running at the back of a diver creating open space across the front and chest area
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