Two coats of Stewart System primer are brushed into the wing. In the first picture you can see what one coat looks like and in the second picture I'm showing the final product. Next up will be sanding the primer smooth and spraying on a few more coats. One thing that did happen that I'm not pleased with is that the paint ran and left drip marks. This primer is EXTREMELY thin and although I thought I was barely putting any on it managed to drip in some spots. I went back and sanded down all the drip marks but you can still see them in the primer. Hopefully they can be sanded and eventually faded away before the final coat goes on.