Yes you can apply enamel clear coat or polyurethane spray coat to laser waterslide decal paper. A comment from my customer, 'Further my enquiry, I tried Tamiya clear enamel, thinned 1:1 with Tamiya enamel thinners. I covered the Laser decals with 3 light coats using my airbrush. The decals held up extremely well, with no shrinking, distortion or any other adverse reaction. I am very impressed with your product'