The compact Atrium 4 loudspeaker produces high fidelity sound quality anywhere you want great sound. Its small size makes it ideal for tight, out-of-way installations. With an aluminum dome tweeter and polypropylene cone driver in each speaker enjoy deep, accurate bass and smoother response. Polk’s patented Dynamic Balance and Klippel Optimization technologies ensure perfect material performance, eliminating driver and tweeter “artifacts” for more realistic sound reproduction at high and low volume levels. The weatherproof cabinet features a rustproof aluminum grille, rustproof aluminum bracket, and stainless steel/brass hardware that can endure seasonal change and provide great indoor speaker-quality sound for years of outdoor listening enjoyment. Quick and easy to install with Polk’s Speed Lock Mounting system.