GET DOUBLE THE BASS IN YOUR CAR IN ABOUT AN HOUR.Simply swap your factory underseat woofers with our plug & play upgrade kit and, get incredibly powerful, tight bass.  TIGHTER, PUNCHIER BASSMore bass without clarity is just noise. Our woofers are not only louder, they're cleaner and clearer. DO-IT-YOURSELF, PLUG & PLAY, EASY INSTALL  Do-it-yourself installation in about an hour, even for a novice. You don't even have to remove your seats! MORE SPACE = MORE FUN Unlike other subwoofer solutions, upgrading your factory woofers takes up no extra space. HOW DO WE DELIVER BASS THAT'S LOUDER, CLEANER, AND TIGHTER WITHOUT CHANGING THE FACTORY AMP?In a word, efficiency. Every watt of power generated by your amplifier yields about 2x the bass output with our woofers vs factory woofers. If you're not familiar with the concept of "efficiency" in audio, just use this analogy: with your factory woofers, your amplifier is like a 200hp motor in a 4,000lb Camry. With ours, it’s like the same 200hp motor in a 2,000lb Lotus Elise - twice the performance with the same power. 2X THE BASSOur woofers are 10 dB+ louder from 20Hz to 60Hz vs factory woofers, resulting in twice the loudness in this critical “sub-bass” range (and over 8x the sonic energy). You won’t just hear the bass; you’ll feel it.NEARLY FLAT FREQUENCY RESPONSE FOR EXCEPTIONAL LINEARITY in the key sub / mid-bass frequency range from 40Hz to 200Hz (+ or - 3 dB). Which means "clean" and balanced bass. 100 DAY IN-CAR TRIAL, FREE RETURNS  Install, audition, and fully experience your new audio gear -- if you don't love it, we'll cover return shipping and give you a full refund (U.S. Customers only). 100% PLUG & PLAY  Installs and fits just like your cars factory woofers, right down to the bolts and factory style plug. (NOTE: 2018+ X3 models and vehicles with “Base” audio systems require slight modification to factory enclosure and may necessitate additional tools) SIMPLE, DO-IT-YOURSELF INSTALLATION  Takes less than 90 minutes and only basic tools, even for a total novice. No complex wiring or additional hardware or installation is required. Simply unbolt your front seats, remove the woofer covers, unbolt your factory woofers, and install ours. That's it! USE YOUR FACTORY AMPLIFIER AND GET EXCEPTIONAL BASS RESPONSE (OR OURS, AND GET EVEN MORE) We utilize your factory amplifier to generate amazing bass response in your car. To do so, we've designed our woofers using technologies like oversized neodymium magnets and lightweight poly cone to maximize every watt of power they generate and translate that into raw output. That means amazing bass response without replacing your amplifier. (Warranty not valid with aftermarket amplifiers or custom audio systems) SUPER TIGHT, PUNCHY MIDBASS  Your factory underseat woofers aren't just subwoofers; they're midbass drivers. That means they play not just the lowest frequencies, but also "punchy" midbass frequencies like snare drums and high bass guitar notes.  Unlike our woofers, which are designed to outperform the factory woofers for both subwoofer and midbass frequencies, other underseat subwoofer upgrades on the market are only capable of playing sub frequencies, not midbass, so you miss a huge portion of the frequency range. FACTORY MATCHED IMPEDANCEDepending on your audio system, your factory woofers come in 2, 4, or 8 Ohm impedance. Our woofers are matched to the impedance of your factory woofers (we have different versions for each) to maximize performance and ensure the longevity of your factory amplifier. UPGRADEABLE DESIGN WITH 160W RMS / 320W PEAK POWER HANDLING PER WOOFER  Even though our woofers are designed to be extremely efficient to maximize the output of your factory amplifier, they're also built for upgradability. You can power them with an aftermarket amplifier of your choice, up to 160W per channel! THE PERFECT MATCH TO OUR LEGENDARY SPEAKER UPGRADES Amazing bass response can transform your listening experience, but if you want the absolute best, overall sound quality and clarity matters too. That's why we engineered the Ghost Underseat Subwoofer Upgrade System to perfectly and seamless match our legendary Stage One Speaker Upgrade Kit.