You cannot breathe directly out of a scuba tank because of the high pressure. A regulator reduces pressure to safe a level that can be inhaled by the diver. A diving regulator has two parts: the First Stage reduces the tank pressure and connects it to the Second Stage which contains the mouthpiece for breathing
The Abyss (MR22) diaphragm first stage features the DFC system and a replaceable HP seat connector. The exclusive MARES DFC system featured minimizes the intermediate pressure drop which occurs in all regulators during the inhalation phase. This pressure drop is greater when higher airflow is demanded of the regulator. The DFC system substantially reduces breathing effort and inhalation resistance, especially during deep dives and under high air flow conditions.
The high pressure poppet was designed for a "2 year or 200 dives" service interval; double the high pressure seat life standard! Compact body, in a modern and smart style, it is made of hot-forged nickel-plating and chromed brass. It is fitted with a preferential intermediate pressure port for connection to the primary second stage, plus 3 other 3/8" threaded LP ports and 2 HP ports with 7/16" UNF thread. The latter are inclined at a 45° angle to allow a more ergonomic layout of hoses.
The balanced diaphragm, first stage regulator is inherently environmentally sealed. The benefit of this type of first stage design is that none of the delicate internal parts are exposed-to-contaminants such as salt, sand, chlorine or pool acids. These environmental contaminants can cause corrosion and mineral deposits to form on the internal mechanism deteriorating regulator performance. A diaphragm first stage regulator requires less-maintenance then regulators that allow contaminates to enter the internal mechanism. For extreme demanding conditions, such as use in cold or contaminated water, the Abyss second stage is made of nickel and chrome-plated brass. These materials offer a number of benefits: ruggedness and thinner walls which allow compact dimensions obtained without using smaller-diameter diaphragms; this result in reduced water drag. The second stage ha an anti-freeze function, which is enhanced by the "radiator action" of the metal.
The Abyss with its Vortex Assist Design (V.A.D.) system: all Mares second stages offer the unique patented VAD system. The air bypass tube conveys air to the mouthpiece creating a swirling vortex with a low pressure area in the center this keeps the diaphragm down during inhalation, giving very sensitive and easy breathing at all depths. The second stage cover features the new "mesh-grid" system for water inflow and outflow, which provides a further performance improvement.
Furthermore, the compact and ergonomic exhaust tee ensures superior hydrodynamic performance and reduced exhalation resistance. The mouthpiece is made of soft hypoallergenic silicone: limiting jaw fatigue and offering a secure fit even after very long dives. Mares developed the Superflex hose after many years of testing and research. The results achieved far surpassed the tests required by EN250. Hose is extremely light weight and exceptionally soft, guaranteeing the maximum freedom of movement and further reducing jaw fatigue. Superflex hose is 1/2" Threaded High Flow hose and is 29.5" (75 cm) in length. Mares Abyss comes with an owner's annual.