Hi all, I have a question about the oxigen bottles. How do I know the type of installed bottle, 39, 76 or 114 cu" and how should it be refilled if the quantity drops below required value. I now have 1630 psi. If it is in a 76 size bottle, this is enough for a 3 man crew, but in a 39 cu" it isn't. Cheers! (ps, the fact that I can bother you with this level of question automatically implies that the NGX is the most incredible add on ever build! thanks again!)