Scubapro R105 Octopus Regulator – Reliable Backup for Scuba Diving

The R105 is ScubaPro's dedicated alternate air source — the backup second stage your buddy breathes from in an out-of-air situation, and standard equipment for virtually all recreational diving. It uses a reliable classic downstream valve with a metal valve housing, a dive/pre-dive VIVA switch, and a high-visibility yellow 39-inch hose with an oversized bore so it is easy to locate and deploy in an emergency.

The R105 connects to any standard low-pressure port on your first stage, making it ScubaPro's universal alternate air source across their regulator systems. The hose attachment is also reversible, so it routes cleanly on either side — which is why divers also use it on pony bottles and deco tanks.

The VIVA dive/pre-dive switch controls the venturi assist. Set to pre-dive, it resists free-flow while the octopus hangs unattended at the surface or during descent — the most common annoyance with backup regulators. Flip it to dive and it breathes with full venturi assistance when it is actually needed.

Follow the interval in your regulator's manual, since manufacturers commonly specify an annual inspection or a set number of dives and many warranties depend on it. A regulator is life-support equipment, so service belongs with a factory-trained technician rather than being attempted at home. Have it looked at sooner than scheduled if you notice increased breathing effort, free-flow, bubbles, or water in the second stage.

Make sure the dust cap is dry and firmly seated over the first-stage inlet before the regulator goes anywhere near water, because water inside the first stage is the leading cause of internal corrosion. Rinse in fresh water without pressing the purge button, since purging while depressurized can draw water back into the second stage. Shake out the water and hang it to dry with the hoses in wide, gentle loops rather than tight bends.

Regulators travel well and are usually best carried in hand luggage where they will not be crushed or lost. A regulator holds no gas of its own, so there is nothing inherently problematic about it on an aircraft, though the airline and security screeners always have the final say. Pack it dry with the dust cap in place, in a padded regulator bag or wrapped in soft gear.

Many modern regulators are supplied as suitable for nitrox mixes up to 40 percent oxygen, which is the widely used recreational industry standard, while anything above that requires dedicated oxygen-clean equipment and procedures. Confirm what your specific regulator's manual states, and follow your nitrox training and your fill station's requirements. Never assume a regulator is oxygen-service clean simply because it looks clean or is new.

A yoke (A-clamp) fitting clamps over the tank valve and is the most common connection across much of the recreational world, while a DIN fitting screws into the valve and is standard in much of Europe and in technical diving. DIN captures the o-ring inside the threads, which many divers consider more secure, but yoke is often what rental cylinders provide. Adapters exist in both directions, so check what is used where you dive before deciding.

The octopus is your backup second stage, carried so you can share air with a buddy who is out of gas, or breathe from it yourself if your primary fails or free-flows. It is normally on a longer, brightly colored hose so it is easy to find and hand over under stress. Secure it in the triangle between your chin and the bottom of your rib cage so it is instantly accessible and not dragging through sand or coral.

Store it fully dry, out of sunlight, with the dust cap in place and the hoses in wide loops rather than tightly coiled. Avoid hanging it by the second stages for long periods, which stresses the hose fittings; laying it flat in a padded bag or hanging it by the first stage is kinder. If it has sat unused for a long stretch, have it checked before your next trip rather than assuming it is ready to dive.

No — that is the point of an AIR2. It combines the inflator and a backup second stage in one unit, so it replaces the separate octopus and removes a hose from your rig. Divers still buy an R105 if they prefer a conventional yellow backup on its own hose, or want an alternate air source for a pony bottle, a deco cylinder, or a rental setup without an AIR2.

It follows the same schedule as the rest of your ScubaPro regulator: a full service by an authorized ScubaPro technician every 2 years or 100 dives, whichever comes first, and it is normally serviced together with your first and second stage. If you dive heavily — 100 or more dives a year — ScubaPro recommends an inspection every 6 months and an annual overhaul. Staying on schedule is also what keeps a registered, qualifying regulator eligible for Parts For Life.