Lanzar 18in Car Subwoofer SVC - IB Open Air Audio Stereo Speaker, 4 Ohm Impedance, Steel Basket, 400 Watt Power, Non-Pressed Paper Cone and Foam Surround for Vehicle Sound System - DCTOA184 300 WATT POWER: This 18in car subwoofer has a power of 150 Watt RMS to 300 Watt peak that will produce high sound resonance. It has 4 Ohm impedance and 30oz high density barium ferrite magnet IB OPEN AIR: Designed as an IB open air subwoofer that will produce bass sound at its best with a high power car audio amplifier. It can be installed directly into vehicle upholstery without enclosure NON-PRESSED PAPER CONE: It is a clean-cut car subwoofer that boasts a black non-pressed paper cone with big foam surround. It will enhance car stereo by producing a powerful audio and keep equipment safe at the same time ALUMINUM VOICE COIL: The speaker subwoofer comes with a 3 or 75mm high temperature aluminum single voice coil or SVC to resist corrosion. Also has a stamped steel basket with a frequency response of 30-1.8kHz and sensitivity of 952dB (1w/1m) 7.33 MOUNTING DEPTH: Easy to install with its 7.33 mounting depth and fits most audio system for cars, boats or RVs. Included are the necessary cables, installation template and manual