DGX Custom - Mares R2XR/SXS O2/Stage Reg Package

In Stock
The DGX Custom - Mares R2XR/SXS O2/Stage Reg Package is an ultra-compact and ambidextrous solution for an accelerated decompression regulator.

DGX Custom - Mares R2XR/SXS O2/Stage Reg Package

Sample R2XR/SXS O2/Stage Reg Package
Sample R2XR/SXS O2/Stage Reg Package R2XR First Stage SXS Second Stage
  • Reliable piston DIN 1st stage with standard BSP G5/8 DIN connector to fit 200 Bar and 300 Bar valves
  • Ambidextrous 2nd stage allows routing from either side of diver plus lateral side exhaust
  • Three LP 3/8-inch ports - one HP 7/16-inch port
  • Includes Mini-SPG, S/S bolt snap, Delrin screw-on DIN cap
  • Assembled, tested and shipped to you ready-to-dive

This DGX Custom - Mares R2XR/SXS O2/Stage Reg Package is suitable for Oxygen Service without the need for additional preparation. The Mares SXS O2 Deco Regulator is an ultra-compact option for an accelerated decompression regulator. A quality piston R2XR DIN first stage together with the SXS balanced second stage featuring an ambidextrous breathing design that can be used on either the right or left side and includes a lateral side exhaust . The package includes a Mini-SPG in choice of PSI or BAR, S/S bolt snap with hose clip retainer, DIN cap, and comes assembled by Dive Gear Express with a green {40 in | 1 m} braided flex hose.

The lightweight, simple, compact R2XR first stage is a classic flow-by piston design by Mares for reliability. The R2XR has four standard size low pressure 3/8-inch ports and one standard size high pressure 7/16-inch port. One of the low-pressure ports now includes the Mares dynamic flow control (DFC) system to provide a constant inter-stage pressure during inhalation with gas flow unaffected by depth, tank pressure, or breathing rate. Tested with oxygen, the Mares R2XR now also includes their Auto Sealing Technology (AST) that stops contaminating agents from entering the interior of the first stage, a valuable safety feature for oxygen service applications! This version has the typical BSP G5/8 DIN connector that will fit 200 Bar and 300 Bar valves.

The Mares SRS Second Stage is a high-performance regulator with an exceptionally compact techopolymer body for ultra low weight. SXS stands for Second eXtra Small and emphasizes the extreme lightness and compactness of this second stage model. The SRS second stage features an ambidextrous breathing design that can be used on either the right or left side and includes a lateral side exhaust for better visibility in all diving positions along with an easy-to-use soft purge button. The Mares second stages also route part of the gas from the second stage valve directly to the mouthpiece through a curved bypass tube that creates a swirling effect or vortex movement. The core of the vortex is a low pressure area that pulls the diaphragm down during the inhalation phase, resulting in a markedly sensitive and easy breathing regulator. This Vortex Assisted Design (VAD) allows for the feel of natural breathing; you do not have the uncomfortable feeling of air being excessively “injected” into your mouth that is typical for high-performance venturi assisted second stages. The VAD also minimizes potential cold-water free-flow due to freezing because the gas expansion inside the 2nd stage occurs in the bypass tube, rather than on the mechanical parts.

Mares a version of the R2XR in Europe with green color plastic accents on the 1st stage bumper, however it also has an incompatible M26X2 fitting. Our US version has black color accents, but IS oxygen service and otherwise identical except that it has the standard BSP G5/8 DIN connector that will fit 200 Bar and 300 Bar valves. The US version of the R2XR is NOT compatible with the M26X2 Nitrox/Oxygen valve outlet mandated ONLY in the European Union by the EN 144-3:2003 standard.

More Information
Brand Mares Extended Range
SKU PK-772004-SXS
Weight 4.000000

Customer Reviews

Tek Tip Warning Image WARNING
According to our suppliers, this product is compatible with oxygen and factory cleaned for use with oxygen. Nonetheless, the 'clean state' of this equipment applies only prior to initial use. Thereafter, periodic inspection and cleaning are a necessity. You must meticulously follow the recommendations of the US Department of Transportation (DOT), Compressed Gas Association (CGA), and other federal/state/local agencies, plus your dive training agency for equipment maintenance, handling, storage, labeling, filling, transport and use of compressed gases. Oxygen-related fires and explosions can result in serious injury or death. Ultimately, you must make the final decision to assume all risks associated with the use of any compressed gases, including those in excess of 23.5% oxygen.


Regulators and Required-stop Accelerated Decompression

Open-circuit technical divers often switch to breathing pure oxygen or a very rich advanced Nitrox mix such as 50%, to substantially reduce their required-stop times as compared to decompressing using just their bottom mix, called accelerated decompression. The depth where the gas switch occurs is relatively shallow, typically {20 fsw | 6 msw} for 100% oxygen or { 70 fsw | 21 msw} for 50% Nitrox. For profiles with very deep and/or very long bottom times, the diver can further reduce their required-stop times with multiple gas switches during the ascent, sometimes called multi-staged accelerated decompression (not to be confused with regulator stages). The depths where the first gas switch occurs in multi-staged deco is relatively deep, typically {100 fsw | 30 msw} using a sport Nitrox mixture and for extreme exposures often the first switch is around {190 fsw | 57 msw} using normoxic Trimix.

Divers on decompression stops are normally at rest and decompression gas regulators are typically configured with only one second stage regulator. Required-stop decompression in general is not an activity that demands high-performance regulators, although it can be in physical overhead environments where the diver must also continue swimming towards an exit. The shallower accelerated decompression depths when using very oxygen rich breathing gases are not at all demanding of regulator performance, almost any regulator would do in theory, but the very rich decompression gas requires the regulator be specifically designated as suitable for use with pure oxygen. Unfortunately, most manufacturers only describe their regulators as suitable for Nitrox mixtures to 40% maximum.

Dive Gear Express offers several specialty decompression regulators all designed and qualified for use with breathing gas mixtures containing up to 100% oxygen, but each suitable for use in differing maximum depth ranges based on their performance. The Dive Rite O2 Regulator is suitable to a maximum depth of { 50 fsw | 15 msw}. The DGX Gears O2 Regulator is suitable to a depth of {130 fsw | 40 msw}. The Mares O2/Stage Regulators are suitable for use to a depth of {160 fsw | 50 msw}. The Dive Rite O2/Stage Regulator and the Apeks O2/Stage Regulator depth limits exceed {330 fsw | 100 msw}. For reasons of familiarity and ease of maintenance irrespective of cost, divers will sometimes choose to use deco regulator versions similar their primary even though their performance exceeds the demands of required-stop accelerated decompression.

Regardless of the capabilities of your regulator, the maximum depth of your dive is also limited by the amount of oxygen in the breathing gas and the partial pressure of oxygen at that depth.