While we were touring Steve and Pam's Arctic Fox
at Buttonwood, I noticed a huge white valve under it. The valve turned out to be the fresh tank drain valve. I did not get any pics of it, but it was easily accessible with the living room slide retracted. Knowing how pitiful the factory Sunline drains are, I may have to attempt a modification and add one of these to the fifth wheel. My only concern, would be figuring out how to attach it to the tank itself.
is the Valterra listing, for the valves.