Robson RT38 is a latex/rubberized compound traditionally used to seal cement that is under ground or to seal steam pipes and pipe insulation. It will always stay pliable, never freeze, and will not crack over time. It is easy to apply with a cheap brush and dries quickly, meaning you can paint your canoe in several days as opposed to traditional canvas fillers that are oil based and can take up to six weeks to dry. White - 1 gallon can will cover most canvas canoes with 3-4 coats. We recommend that a high build primer paint be applied over the filler to get a smooth surface through sanding. See Pre-Kote on the storefront.