Dual regulators must be used when diving double tanks with a manifold, a single tank with a pony bottle, or when using a single tank with a Y or H valve. One first stage and second stage must be used with each tank. A pressure gauge and inflator hose is required with any of these setups. When using a manifold double tank setup, only one pressure gauge is required. In addition, one of the regulators should be using a long hose (5 or 7 feet) with the second stage. The long hose length is determined by the type of configuration and type of diving you’re doing. Typically cave divers use a seven-foot hose that they breathe from and pass to a diver in an out-of-air situation. In open water diving, typically a five-foot hose is all that is needed. You should breathe from this hose on your primary tank and hang your backup regulator around your neck.
Cost: 2 x single regulator purchase