Nitrox Ready and suitable for use with air or argon, the DGX Gears FIRST Regulator has a depth compensating balanced piston first stage with an intermediate pressure of 120 psi and includes an over pressurization relief valve (OPV). This means the output pressure (aka “intermediate” pressure) is a constant 120 psi unaffected by changes in supply pressure or depth. Primarily intended for use in inflation and light SCUBA applications such as pony bottles and oxygen accelerated decompression, this first stage provides unusually good performance for such an inexpensive system.

Measuring {4.0 in x 1.5 in | 10.2 cm x 3.8 cm}, the regulator offers three standard size low pressure 3/8-inch ports (one is used by the OPV), one standard size high pressure 7/16-inch port. This regulator has the typical BSP G5/8 DIN connector that will fit 200 Bar and 300 Bar valves.

On dedicated inflation systems or on breathing systems where the second stage has a flow stop cut-off installed, there is no regulator second stage to provide relief should the high pressure seat begin to fail and the intermediate output pressure rise. Without a way to relieve the pressure, the device could begin inflating rapidly or the low pressure hose could rupture. Best practice in such configurations is to include the over-pressure relief valve to provide the same relief function as a normal regulator second stage. If you configure the FIRST with a normal second stage, then the OPV is unnecessary and may be removed if you wish.