The Proficient Signature In-Ground Subwoofer features a waterproof HDPE enclosure which is dunk tested before shipment to ensure against leaks. The port and canopy assembly is designed to move air in an even 360-degree pattern. The critter-proof aluminum mesh grill cover allows for maximum air flow while protecting the entire port assembly against bugs, animals and debris. Waterproof HDPE enclosures are made from the same material used in municipal water supply lines. We dunk test every subwoofer before it ships to ensure a waterproof enclosure. The internal design of the port and canopy assembly spreads moving air evenly in a 360-degree pattern, reducing air turbulence and eliminating annoying "port noise." The port assembly is covered by an aluminum mesh grille that allows unrestricted airflow yet prevents intrusion of bugs, animals and debris. The subwoofer's low impedance 8Ω design is the best option when it comes to delivering jaw dropping performance in an outdoor environment. Optimized for use with PAS-AW-LS-4 or PAS-AW-LS-6 landscape speakers.