The great beauty of Phil's bellows solution is that it requires no power and very little maintenance. When the world is going to crap in your PSUB, the will still work even with a loss of power. In the tech sheet for the electronic valve, it notes that nylon is used for construction and this is incompatible with 100% O2. R/Jay Resepectfully, Jay K. Jeffries Andros Is., Bahamas Save the whales, collect the whole set. -----Original Message----- Alan, Interesting units. You'll need to confirm that they are compatible with O2. I note in the text that they only mention specify compressed air. Jon |