Check the listing for details. Mission Models Polyurethane Mix Additive 2oz MMA-001. Condition: New. Listed at 10.79 USD. Mission Models Polyurethane Mix Additive 2oz MMA-001Add just a couple drops of the polyurethane to your thinned paint. Just one or two drops is all you need. The poly greatly increases flow from your airbrush on top of the already amazing flow and leveling of the paint. The results are further leveling, durability, increased sanding capabilities and will also add a very light eggshell finish.When spraying straight from the bottle without thinning your paint add one or 2 drops and adjust your psi accordingly. You can pull ultra fine lines. Figure painters add a drop for slower blending. Adding too much polyurethane will cause the paint to dry much slower.Do not add poly to the Mission Models Primer.Remember less is more. Example. If you have 20 drops of paint in your epoxy mixing cup add 2 drops of poly.We advise hand mixing vs shaking established in 2001 Mission Models strives to bring you the best and most unique products on the market today. Mission Models manufactures all products in the USA. We are a team of modelers, business professionals and artists.