Da Vinci's Copal Painting Medium Substitute is formulated to dilute oil paints in glazing applications, and for thin applications in general. It dries faster than linseed oil, but slower than alkyd resins.

Grumbacher Copal Painting Medium is made with a modern synthetic copal resin. When added to oil colors, it improves flow, accelerates drying, and imparts hardness and a high gloss to the dry paint film.

Prepared from finest synthetic copal gum. Improves paint flow, and speeds drying. It makes a tough final varnish, giving excellent protection for finished paintings.

Weber's Copal Medium is excellent for glazing, thin or impasto painting, and wet-on-wet techniques. It may be thinned with Turpenoid or turpentine. Copal Medium is prepared from synthetic and natural resins, and refined turpentine.