Boasting the simplest backflow preventer design, Atmospheric Vacuum Breakers (AVBs) are also the least expensive—but only if you have less than six control valves. Though atmospheric vacuum breakers backflow devices aren’t designed as a whole-system backflow prevention valve, they’re still premium quality, highly efficient devices that stand as a paramount solution for preventing backflow contamination, thereby ensuring the utmost purity and safety of your water supply.