Made of mica-polypropylene and are built for added protection against the elements associated with boating. Designed to withstand vibration and temperature changes, as well as exposure to moisture and salt air. Power handling is 150W (RMS) and 350W (Peak) for solid, powerful bass. Quantity: Single Cutout size: 8 3/4"dia. x 4 7/8"D Style: Flush mount Impedance: 4 ohms Magnetic Shielding: No Polypropylene with santoprene surround Waterproof Rating: Water-resistant Warranty: One year