Johns Manville Zeston® 2000 Series Color standard gauge PVC fitting covers are manufactured from high-impact, polyvinyl chloride material designed to provide abuse-resistant protection for insulated piping. The one piece color fittings are available with or without Hi-Lo® Temp Formaldehyde-free fiberglass inserts. Our wide range of products and accessories enable the contractor to design, fabricate and install a complete system with a quality finished appearance.