In looking to have an O2 system I found one online that was open source. I built it. There were some complications such as needing to order valves to my German friends mothers house. Some other items. Overall fun build. <a target="_blank" rel="noopener noreferrer" href="http://nortd.github.io/WaveGlide/">http://nortd.github.io/WaveGlide/</a><br><br>My friend and I looked to find ways to correct some of the issues, his work can be found here. <br><a target="_blank" rel="noopener noreferrer" href="https://github.com/jlovering/WaveGlide2.0">https://github.com/jlovering/WaveGlide2.0</a>