The Apollo® model RP4A/RPLF4A lead free* & non-lead free series reduced pressure backflow preventers provide maximum protection against back-siphonage or backpressure from substances that are hazardous to the potable water supply. The top accessed modular check valve cartridges provide captured springs, replaceable seats, and reversible silicone seat discs. This made in America assembly features ball valves with stainless-steel handles and trim as standard and carries the five-year Apollo® factory warranty. Maximum protection against back-pressure/back-siphonage. Modular check valve cartridges w/ easily replaced parts. Reversible/removable chloramine-resistant silicone seat. Slow head pressure loss. Top mounted test cocks. Threaded test cock protectors. Internal sensing passage. Modular captured spring relief valve. Lead free option standard with full port ball valves with stainless steel handles. Corrosion resistant. 5 year warranty.