Hi, I'm a game warden and fisheries biologist in Oklahoma. I'm researching shallow water o2 rebreathers to use in my work observing and filming spawning stream fish and found your ingenious homebuilt unit. Would you mind sharing the specifics of your build? 90% of my time is spent in less than 2' of water and 100% less than five feet. That said, you may wonder why I need a rebreather, but I need to lay very still for long periods so that fish become acclimated to my presence. I'm well aware the dangers of diving and o2, half a lifetime ago I was a commercial diver in the gulf of mexico for the offshore oil industry. Again, I have no desire to use the unit for anything more exotic than laying on bottom observing spawning fish in water less than waist deep. I'm anxious to hear your thoughts and very much look forward to hearing from you. Thanks so much, Brandon Brown Kingston, OK madtom@itlnet.net