Poseidon 1st Stage Xstream Black G5/8” - Poseidon has recently introduced the new Xstream "Black" first stage, which is both oxygen compatible and oxygen clean. The cosmetic difference is the entire regulator is black color rather than silver color. The Black is suitable for all mixtures including Nitrox and Trimix. The Xstream first stage uses a unique synthetic ruby sphere that virtually eliminates high pressure seat wear that is common in knife edge design seating systems. The Xstream first stage also uses a rolling diaphragm design that eliminates any restriction in movement, which creates a smooth transfer of gas from the first stage to the second stage. This rolling diaphragm design further creates a insulating barrier so there is no need for an additional environmental kit. The Xstream has five low pressure standard 3/8-inch UNF ports and two high pressure standard 7/16-inch UNF ports.

Please note that when this first stage is sold "raw" as received from the factory and not as part of a package that includes a second stage, it will have four of the five LP ports plugged (i.e. one LP port will be open) and both HP ports will be plugged.