http://www.hansgrohe-usa.com/18920.htm http://www.hansgrohe-usa.com/18920.htm Not sure what "rain brain" is, but their non-electric thermostatic valves do a lo

http://www.hansgrohe-usa.com/18920.htm http://www.hansgrohe-usa.com/18920.htm Not sure what "rain brain" is, but their non-electric thermostatic valves do a lot of what you want (we have them in our house).