After crawling through some small holes in a wreck last week, it has reknewed my interest for BMCL for my Meg. What options are out there that still have a working ADV.

I would prefer something along the DaveT lungs that I have seen DrMike(and Phi??) with or some other design without a hard case but am open to options...

I think simply turning around the lungs doesn't seem viable for manual addition of gases or the ADV but correct me if I am wrong...

Cheers