<html><head></head><body><div class="yahoo-style-wrap" style="font-family:Helvetica Neue, Helvetica, Arial, sans-serif;font-size:13px;"><div dir="ltr" data-setdir="false">Hi All, I am looking for ideas on how to make a automatic O2 feed similar to the DW bellows add. I want a non electronic system. I was thinking about a scuba second stage regulator conversion, that senses negative pressure to release O2. Sean???</div><div dir="ltr" data-setdir="false">Hank</div></div></body></html>