Looking at the picture I see the adapter connects to the primary second stage. The SE version has an oversized hose , like mares , and same era I guess (seems like this logical conception didn't caught for practical reasons). So , it makes sense it's from 2004.
I have two Conshelf that couldn't try due to too many regulators, but I think that a regulator being around for such along time used by US navy and IDF too speaks for it self and no advocacy.
They are sold pretty cheap of eBay and here at SB so I guess it's hard to go wrong with it.
Bug hey , no bells and wistells from marketing perspective.