303 Protectant only slows down the deterioration. After paying $160 for one replacement decal, seemed like good idea to find out what the Pros use. Through a friend of a friend in the graphics business I found out that there is a coasting specifically made to protect decals, i.e., Marabu Clear Shield. The stuff costs $40 a quart, but a quart could cover a LOT of decals. However, the container says "for professional use only", so maybe you cannot buy directly, and need to find a buddy in the business to obtain. Dunno. The stuff is water clean up, and made my faded decals look much better, even made the color come back on my front decal which was severely sun-damaged. I shaved off all the curling bits, and went over each decal completely with the stuff, paying attention to the edges. After 24 hrs, I went over all the edges again. The trailer now looks almost new (its a 2007). The stuff forms a plastic-like clear shield. I guess that is why they named it "clear shield". Just thought I'd share. And, no, I don't work for Marabu, I don't work for anyone, am totally retired.