The ideal octopus for the Abyss Extreme regulator. The new Abyss Extreme octopus is a heavy-duty octopus for demanding dives with an all-metal design for maximum performance. The all metal octopus is coated with a special fluoropolymer resin finish on the second stage case and all key components to prevent ice crystals from forming in extreme cold conditions. Nitrox-compatible to 40% oxygen.