I watched a show the other week on a husband/wife team (can't remember their names) that are pretty famous, by their count, in the area of underwater video and film. Their scuba equipment consisted of a large unit they would wear on their back that contained two ball-shaped canisters of air/nitrox, with a rather large circular filter, and the unit would recycle their expended air, enabling them to enjoy deeper bottom time. Sorry - but that's the best description I can give.
Any idea what this equipment is or where to look for it?
Any idea what this equipment is or where to look for it?