I put this
Shurflo Accumulator Tank in my TT however if I did not go to the new expensive pump that "does not need it" I would use the
2 gal tank. These tanks are not hard to install. Just make sure you have the correct fittings before you start. They do help prevent the pump surgging when small amounts of water are pulled at the faucet. I pulled from the Camping World pages because they were available.
Good luck and Tow Safe.