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 ZEAGLE ZO Onyx Regulator outperforms many, much more expensive regulators with outstanding reputations - why? The Internal-Structure allows Direct-Airflow through the 1st Stage, providing Lower-Turbulence for Outstanding-Performance. ZEAGLE`s Conical Precision Stainless Steel High-Pressure Valve Advanced Polymer Seat provides much Greater-Reliability and Service Life compared to conventional designs, while Improving-Responsiveness and Performance at All-Breathing-Rates. ZEAGLE`s Regulators are US made, Built Under-Strict Controls for Quality in ZEAGLE`s Own-Factory, using State-of-the-Art Equipment and Procedures. Your Regulator is one of your Most-Important-Pieces of Gear. No matter what kind of diving you do, you can do it better with ZEAGLE. The 30" (76 cm) and is 3/8" Threaded Braided Low Pressure Hose provides High Flow and Tremendous-Abrasion-Resistance while having Great-Flexibility. The Compact Exhaust Tee, Advanced Black Satin Chrome Finish and Light Weight Construction give the Onyx a beautiful presence. The Black Chrome Plated Marine Brass First Stage Regulator Body is a Balanced Diaphragm Design which is Inherently Environmentally Sealed. The diaphragm membrane transmits the pressure changes to the internal mechanism eliminating the need for the surrounding water to enter the intricate mechanism. The benefit of this type of first stage design is that none of the internal parts are exposed to contaminants such as salt, sand, chlorine or pool acids.