OK, yup we had an issue with plain 'ole communication LOL. Hazard of using an online forum...
Yes, I meant the 4" square vinyl that was featured in the first/second post. Very popular mod and I ran out to do it when I had a TT. But my Rhino fittings wouldn't fit. And I couldn't find the larger size readily available where I live. The Rhino doesn't fit in the bumper either.
I didn't want the larger size anyway b/c of weight. Especially now that I have a TC I would only try and put the 4" under the wing, not the heavy stuff.
But now I don't need it al all b/c I have a 5 gallon Thetford Curve porta potty and the shower takes one of those grey water adater caps so I use a regular garden hose for grey water now.