Help ID primary reg

[jacked_72]

Anyone have a good idea what make this primary is? It looks like the USD Conshelf series, except for the IP adjustment at the bottom requiring a hex key. That makes me think its Mares, but the yoke screw screams USD. Other possibilities based on the secondaries attached to it and SPG are Sherwood and White Stag. I doubt its a Sherwood. Anyway, if you know, please let me know.

 

[Paladin]

Looks like a Conshelf XI. The XI has a hex key adjuster.

 

[jacked_72]

I took it apart. I don't think its a USD. Every one of those that I've seen has a square one of these (what ever its called). This part is round. I'm guessing Mares, but I don't have enough experience with Mares to say with any certainty.

 

[Paladin]

This is an old Conshelf XI. Trust me, I have several of them and service them myself. The balance chamber was round in the older Conshelf versions and square in the later models. I have regs of both types. Either one will work.

 

[herman]

Agreed, that is an older Conshelf, not sure what model but a Conshelf none the less. The balance chamber looks just like the ones in the Royal Aquamaster DH reg and would be correct for a reg of late 60 vintage. In any case, a fine reg to rebuild and dive.

 

[jacked_72]

Thanks guys. I hadn't seen the round balance chamber before. Good to know. I appreciate it.

 

[John C. Ratliff]

The only thing I can add is that this is probably from the early 1970s, and not the late 1960s. The 1973 USD catalog shows the Conshelf XII with approximately the same configuration (though the hex nut is not showing in the photo).

SeaRat

 

[Paladin]

The Conshelf XI and XII were identical except that the XII was the first Conshelf with the slotted adjustment screw instead of the hex nut. My XIs all have the hex and my XIIs have the slotted adjustment.