This 4 inch lead free double check valve assembly is designed to prevent the reverse flow of contaminated water of non-potable quality from being pumped or siphoned into the potable water supply due to backsiphonage and or backpressure in accordance with national plumbing codes and water authority requirements. This assembly consists of an epoxy coated cast iron body construction, non-rising stem resilient seated gate valves, test cocks, and a modular check design for easy maintenance with center stem guide. The captured spring is accessible through a bolted cover plate. It is ideal for protection at cross-connections identified as non-health hazard applications and from other contaminants found at the service line entrance.