BOSS Audio MR105 Marine Subwoofer - 1000 Watts Maximum Power, 10 Inch, Single 4 Ohm Voice Coil, Easy Mounting (Sold Individually) CONE: Made From Polypropylene, The MR105 10 Inch Marine Subwoofer Provides a Resilient And Durable Material That Can Offer Great Sound With The Advantage Of Long Lasting Subwoofers VOICE COIL: Our Voice Coils Are Able To Withstand High Temperatures Yet Maintain Its Strength And Fatigue Properties. Making Our Voice Coils With This Material, Gives Our Speakers The Advantage Of Longer Pay Times With Lower Weights SURROUND: We Use Rubber In A Lot Of Our Subwoofers. It Has The Ability To Endure Much Punishment Without Any Sign Of Damage. It Compliments The Whole Structure Of The Speaker By Allowing Constant Abuse Where It Is Most Needed, Without The Wear And Tear SPECIFICATIONS: Resonant Frequency - 43 Hz, Sensitivity SPL (1W/1m) - 87 Db, Basket  Plastic, Mounting Hole Diameter  8.8, DIMENSIONS: Depth 11.1 x Width 11.1 x Height 5.1 WARRANTY: BOSS Audio Systems Provides a Powerful 3 Year Platinum Online Dealer Warranty So Long As The Purchase Is Made Through Amazon Dot Com