The AST-22D works in the Dive Rite Optima, KISS rebreathers, Hammerhead,, rEvo, Liberty, original Inspiration, Prism 2 and Explorer MK2, PoseidonMK6/MK7 and Discovery VI. It also works in the following oxygen analyzers: Nitroxbuddy, OxySpy, Hydrospace Explorer, Oxy2 and Lifeguard.