Apeks diving regulators and equipment
21 January 2019   
Product Types

First Stages

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Our first stages represent the cutting edge of design. We have overcome complex engineering constraints and produced equipment that achieves top performance and yet remains uncomplicated, guaranteeing greater reliability and lower cost maintenance and service. The first stage - the powerhouse of your regulator - reduces the high pressure air stored in your cylinder to a controllable intermediate pressure of 9.0 - 10.0 bar. The air then flows along the medium pressure hose to the second stage (demand stage).

Apeks manufactures an extensive range of first stages to meet the needs of every diver. All are of pressure adjustable, depth compensated, balanced diaphragm design and supply air at exactly the right pressure. As the diver descends the demand for gas increases and to maintain the supply, the intermediate pressure increases relative to the water depth. In the Dry-Sealed System hydrostatic pressure, acting on the outer sealing diaphragm, is transmitted to the primary diaphragm via the load transmitter. These first stages utilize a unique over-tracking (over-balanced) diaphragm design, where the intermediate pressure supplied to the second stage increases more than traditional balanced models, as the diver descends to greater depths. This increased intermediate pressure compensates for the increased density of your breathing gas by allowing a larger volume of gas to flow through the system on demand. The result is superior breathing performance regardless of depth. The over-tracking diaphragm design is found on Apeks Black Pearl, ATX 200, ATX/TX100, ATX/TX50, ATX/TX40, and TX40/DS4 first stages. Diaphragm first stages have a number of advantages over piston type first stages, especially when combined with Apeks Dry Sealed System*. They offer outstanding gas flow, easy maintenance, simple adjustment of intermediate pressure and a sealed mechanism totally protected from all types of contamination and freezing.

* Apeks invented the first successful 'dry' environmentally sealed system and all our regulators intended for cold water use, have this system as standard. Apeks manufactures an extensive range of first stages to meet the needs of every diver.

The complete range of Apeks First Stages

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