Technical divers need redundant safety back-ups on most all their equipment to assure the safest dive techniques allowed. A first stage regulator should work well when it is maintained properly, yet if it does malfunction added safety features can make the difference between a controlled emergency and a diving accident. Incorporating a safety relief valve on your first stage regulator allow an over pressurization of the 2'nd-stage hose nearly imposable. XS Scuba's Deluxe Over-Pressure Valve (OPV) is an adjustable all stainless-steel constructed valve. This compact relief valve is designed to releases pressure in the event of an over pressurization of the first stage regulator. Easy to install into a standard 3/8-24 UNF low pressure regulator port and is adjustable from 150 to 250 psi (10.34 to 17.24 bars). OPV is factory set at 175 to 185 psi (12 to 12.75 bars) and comes with machined Delrin cap to protect the adjustment point. OPV is factory cleaned and comes with Viton O-ring for use with enriched air Nitrox.