Atrium Series Outdoor Loudspeakers offer the ultimate in flexibility, reliability and high fidelity sound quality for all your outdoor spaces. They give you the freedom to put speakers anywhere you want high performance sound. Sure, there are lots of "outdoor" speakers out there. But look at the fine print. Many of them are suitable only for placement in sheltered locations. Atriums are true four season loudspeakers. Polk's Atrium Series speakers meet or exceed military specifications for environmental endurance. The tests have coded names like "ASTM D5894-UV Salt Fog," "Mil standard 810 Immersion" and "Mil standard 883 Method 1009 8 for salt and corrosion." But passing them means that Atrium speakers can withstand some of the worst that Mother Nature can dish out. In addition, stainless steel, brass and aluminum hardware ensures years of rustproof reliability.