Consolidated Aircraft Coatings Flattener is a liquid product with silica flattener added. It is used to reduce the gloss of Poly-Tone, Enamel, Ranthane and Aero-Thane. Adding Flattener in increasing amounts can result in semi-gloss or full military flat, depending upon the percentage added. Flattening is an inexact science; it is always best to spray a sample then let it dry to ensure you are achieving the desired flatness.