That fitting was used for the first SPG's, which had the hose fitting at the back and no need for a swivel. When the bottom fittings were made the swivel was also made so they could be faced conviently when used. The actual fitting on the SPG's were the same and older hoses could be use with new SPG's. Industrial standards being what they are, I'll bet they are still interchangeable, although I haven't rooted through my dive locker to check.
Like modifying a natural gas regulator to breathe air underwater, we all know how that turned out.
Bob
Thank you for giving me a reason to check! You're right and I didn't know it prior to dive locker digging moments ago:
The non swivel spg is just the standard pipe fitting. (SAE Straight Thread 7/16-20In I assume from comparing it to my other known fitting)
Old hp hose (original?)
Recent short hp "SCUBA" hose:
I recall a @Sam Miller III dive history trivia question a few months back which referenced the sea-vue. An added reason to post this up.
The old hose also fits a new spool and seats with a semi new SPG as well.
Industry standards!
Cameron
Ps. In an attempt to stay on topic even though I got excited: the old hp hoses screw into a LP port, but the orifice appears to be larger than the newer hoses I have on hand.