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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

Hollis H-O2 First Stage Only Regulator


Call on the HO2 1st Stage for an oxygen regulator that will never stop performing. 

Out of Stock

The Flow-By Piston Design is the only true Fail-Safe First Stage Design on the market. The Piston will automatically move Downstream from the High Pressure Air coming from the Scuba Cylinder if there is an unexpected malfunction of the High-Pressure Seat.

Bulletproof Hollis HP5 First Stage Design
Non-Balanced Flow-By Piston
Fail-Safe First Stage Design
300 BAR/4500 PSI DIN Connection
DIN Hand-Wheel Connector: Oxygen Green for Easy Identification for Oxygen-Use-Only
Material: Durable and Corrosion Resistant Marine-Grade Chrome Plated Brass
4 LP 3/8" Threaded Ports
1 HP 7/16" Threaded Port

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