LeakGuard OneShot A/C supplement from CPS Products, Inc. combines LeakGuard sealer along with ExtenDye; a premium AC dye and oil enhancer, to effectively find and stop leaks. LeakGuard is an oil based sealer that will not harden, crystalize or clog AC systems, or recovery equipment. ExtenDye is super concentrated dye that is designed to locate leaks. The ExtenDye additive package increases lubricity of AC oil by over 50 percent, reduces friction between metal components by 110 percent and prolongs oil life, according to the company.