Atrium5 loudspeaker steps up the sonic performance with a 5-inch driver that produces high fidelity sound quality anywhere you want great sound. The speaker’s mineral-filled polypropylene cabinet can stand up to the elements year round. And its new one-handed Speed-Lock™ mounting system makes installation fast, easy and safe. The mounting bracket even enables a 45° angled mount aiming down into a listening area. 5-inch (12.7cm) long-throw mineral-filled polypropylene cone driver with butyl rubber surround pumps out surprising bass response from a compact design. 3/4-inch (19mm) anodized aluminum dome tweeter with rubber surround and neodymium magnet for better power handling and smoother response. Broad coverage baffle design, adapted and applied from our current Atrium design but with subtle improvements in the new Atrium series. You want to fill a large open outdoor space with big, full-range sound, new Atrium series has a more steeply-angled baffle design that maximizes critical mid- and high-frequency dispersion over a large area, without sacrificing the detail. Polk all-weather certified, Atrium series speakers exceed baseline industrial and military specifications for environmental endurance (ASTM D5894-UV Salt Fog, Mil Standard 810 Immersion, Mil-Std 883 Method 1009.8 for salt and corrosion.). Aluminum grilles and bracket, with stainless steel and brass hardware, no rust ever.