HEPVO valve replaces "P" traps.

We have a 2010 Keystone Passport BH250.
Has anyone installed HEPVO valves to replace the "P" traps under sinks and bathtubs? I've heard they are popular and space-saving. Any thoughts? JW

[Flyguy]

I for one have not heard of this, but I did some web browsing and found this you tube video which explains the device. Here's the link for those that are just as much in the dark about this as I am:

http://www.youtube.com/watch?v=tDNh7lfcIYQ