Colourless liquid for use on Solarfilm, Solarspan, metals and some other plastics as an etch primer. Improves the adhesion of many iron-on, adhesives, paints., etc, to Solarfilm, etc. When applied to Solarfilm before ironing on an overlapping piece of Solarfilm, the seam is much stronger. Resists the entry of fuel and stops the edges lifting even after prolonged use. The edges of canopies can be treated with Prymol to assist the adhesion of glues to the canopy material.