Towboy, all it says on the roll is leak repair tape (white). All I done was wash the roof good, left the caulking on that was there already. The Eternabond tape is four inches wide, so I made sure each side had at least an inch of fiberglass surface so that it would have something to stick to, and just laid it on top and pressed it down. It was easy to apply and you do not ever have to worry about a leak again. My wife got up on the roof and helped me some in keeping the tape going straight over the seams. Best to do it in the summer because the heat will make it even tackier.
The rolls of tape that I bought were 4"X 25'. Water leaks can be a nightmare to find sometimes. And I am 72 years old and I just did not want to be getting on top of that coach every year to reseal with Dicor. Trip one time up there and it is all over.
When you get on the Amazon website, go to the bottom of the page and click on #1 Eternabond. It will tell you all about the tape and even will show you pictures on how to lay it over the seam. Make sure you get the white tape if you have a white fiberglass roof.