Amazon.com: DC Audio LVL3-M2 12" Level 3 900W/1800W Dual-2-Ohm Car Audio Subwoofer/Sub : Electronics
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Pyle Active Down Firing Subwoofer - 10 Inches, Ported Design with High-to-Low Input Level Controller, Invisible Down-Firing Speaker, Color Black, Built-in Convenience - PSUB10A - Walmart.com
10-Inch Low-Profile Amplified Subwoofer System - 900 Watt Compact Enclosed Active Underseat Car Audio Subwoofer with Built In Amp, Powered Car Subwoofer w/ Low & High Level Inputs - Pyle PLBX10A - Walmart.com
Car Audio Slim Active Subwoofer – Pyle USA
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DC Audio Level 5 Elite 12 M5 3500w Subwoofer - SSA STORE
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3500W DC AUDIO LEVEL 4 DOUBLE SUB PACKAGE (PLEASE READ DESCRIPTION FOR DETAILS) - Down4Sound Shop
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DC Audio M2 Level 2 10 Inch Subwoofer - Price, Review, Specs – Droppin HZ Car Audio