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If you can't find one for the Atmos AI, check with the folks at Pelagic Pressure Systems/Aqualung to see if the boot for the i550 might be compatible. It looks like it might work. Both the Atmos AI and AL i550 are/were made by Pelagic Pressure Systems. If you can get in touch with one of the tech guys at PPS, that will likely be your best bet. They solved a problem I had with the battery hatch covers on my Atmos AIs.