DESC: The TR400-CXi is a perfect drop-in upgrade for most vehicles that accept a 4-inch round or 4x6-inch oval speaker. Designed for smooth, balanced output above 70 Hz and capable of handling the power of todays high-powered head units or a small amplifier, the TR400-CXi delivers impressive sonic output and quality. A smooth-sounding, 1/2-inch textile dome tweeter with ferrofluid cooling and a neodymium magnet delivers smooth, accurate high-frequency response. The injection-molded, mica-filled, polypropylene woofer has been painstakingly engineered for gradual and smooth upper-frequency rolloff, resulting in a seamless transition to the tweeters frequency range.