KlearVar® Post-Cat Clear Conversion Varnish represents the latest in durable, long-lasting wood finishing technology. KlearVar® is a high solids, water white, non-yellowing, post-catalyzed amino alkyd finishing system that leaves a unique, smooth-to-the-touch finish. It is a low odor, self-sealing, easy-to-apply formulation that has exceptional resistance to water, solvents and household ...CrystalVar™ 275 VOC Clear Conversion Varnish may be used as a self seal system. Do not use as a topcoat over lacquer sanding sealers, undercoaters or primers. Use with 310607 CrystalVar 275 Sealer or self-seal. Do not use alkaline based products to clean surfaces finished with CrystalVar 275 VOC Clear Conversion Varnish. As the term ‘Varnish’ applies to a broad variety of finishes, we will try to stick to traditional definitions. Traditionally, varnish is a combination of a resin, a drying oil and a solvent (or thinner). In the simplest formulations, varnish dries by the rapid evaporation of the solvent, allowing the resin to harden. For exterior use, a long oil varnish is best. Because it is more flexible, the varnish will expand and contract with the wood as changes in temperature and humidity take place. A medium oil varnish will not move as much and therefore as the wood moves and the varnish does not, the varnish will soon start to crack and peel.