Series WATTS®Box Backflow Preventer Insulated Enclosures protect backflow prevention assemblies, such as PVBs, double checks, and RPZs, that are subjected to freezing conditions. Series WATTS®Box enclosure consists of reinforced aluminum or fiberglass construction, providing access through lockable doors and/or a hinged lid for testing/certification purposes. It has a means for a permanent anchor and is completely removable for maintenance purposes. It has drain openings that are protected against severe weather conditions. Series WATTS®Box is available with or without insulation and heat in various models and sizes. Thermostatically protects to -30 deg F.