Gamblin Gamvar Picture Varnish
Gamvar is billed as "the easiest way to make your painting look better."
It is great for giving oil (or acrylic) paintings a unified, protective finish. It comes in three different finishes: matte, satin, and gloss.
Gamvar Varnish saturates colors in your painting and gives your work a unified and protective surface. Developed in collaboration with the National Gallery of Art, Gamvar can be easily and safely removed with Gamsol. Gamvar is virtually odorless and ready to apply. Brush apply. Do not spray. All Gamvar can be applied when the thickest areas of your painting are thoroughly dry and firm.
Gamvar won't yellow over time. Unlike traditional damar varnish, Gamvar is made from a synthetic resin, and it's entirely clear.
Gamvar can be applied much sooner than traditional varnishes. Instead of waiting six months or a year to apply a traditional varnish over an oil painting, you can apply Gamvar when the thickest areas of your oil painting are touch-dry (tack-free). A good rule of thumb is to wait four weeks to apply Gamvar.
Apply it thinly: one coat. If you apply it too thickly, it can look streaky or cloudy. It will be dry within 18-24 hours.