OMS Dive Gear AirStream 1 (DIN) Style Chrome

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.

It has four low pressure ports and two high pressure ports. The LP ports are angled 30 degrees down and 23 degrees out, which routes the second stage and inflator hoses over the shoulders, and the HP ports are angled 45 degrees down so a gauge or transmitter hose stays closer to the hip. The angles are forged into the body for cleaner hose routing and less drag.

Yes. OMS publishes the Airstream first stage in an INT/yoke version as well as this 300 bar DIN version, plus PVD-finished DIN and yoke versions. This listing is the chrome DIN model; OMS publishes it as the standard non-PVD Airstream First Stage DIN. Contact DiveCatalog if you need help confirming which fitting matches your cylinders.

Yes. The first stage is environmentally sealed, so water and contaminants stay out of the working mechanism, and OMS forges a heat transfer feature into the front of the body to improve cold water performance. The overbalanced diaphragm design also increases intermediate pressure as depth and gas density rise, which supports gas delivery on deeper, colder dives.

OMS pairs this first stage with the OMS Evoque second stage, sold together as the Airstream Evoque set. With four low pressure ports you can also add an octopus, a BC inflator hose and a drysuit inflator hose, and the two high pressure ports accept a submersible pressure gauge or an air-integrated transmitter. Call 888-701-4017 for help building a set.