Polk Audio DB691 6 x 9 Inch 3-Way Speakers w/Gold Woofers - Pre-owned pair Product Features: Dynamic Balance: Dynamic Balance is a proprietary Polk Audio technology using laser imaging to determine what combination of speaker materials create the least amount of resonance. Eliminating resonance in speakers results in a wide, smooth response and low distortion. Rubber Surrounds: The inner and outer woofer surrounds are Santoprene rubber, to keep water from leaking through the speaker. Tweeters: The tweeter and super tweeter material is Terylene, a brand name of polyethylene terephthalate (PET). Neodymium Magnets: The speakers' neodymium magnets offer exceptional strength to performance ratio and are small and lightweight. Crossover: The crossover components are coated with epoxy to prevent corrosion. The low pass filter is 1st order (6 dB/octave), the high pass tweeter filter is 2nd order (12 dB/octave) at 3.5 kHz, and the high pass super tweeter filter is 3rd order (18 dB/octave) at 4.5 kHz. Ultra-Marine Certified: Polk MM1 Series speakers are tested to withstand exposure to salt-fog, UV rays, and humidity, so they'll work well in boats and cars. Specifications: Frequency Response: 30 - 40k Hz Maximum RMS Wattage: 150W Peak Power Handling: 450W Top-mount Depth (Inches): 3-1/8" Speaker Size: 6x9" Design: 3-Way Tweeter Design: 1" Dome Impedance (Ohms): 4 Tweeter Composition: Terylene Fabric Woofer Composition: Titanium Coated Composite Woofer Surround: Santoprene Rubber Sensitivity (1W at 1 meter)