Pioneer TS-A1072R 4-Inch 3-Way 150-Watt Speakers (Pair) Carbon Graphite IMPP Cone Woofer using Interlaced Aramid Fiber Foamed Rubber Coated Cloth Surround Glass-Imide Voice Coil 15/16" Light Weight Balanced Dome Midrange Design with Neodymium Magnet and Magnetic Fluid 3/8" Dome Tweeter Custom Fit US/European Compatible Basket Design Specificatons: Watts MAX. Music Power 150 Watts Watts Nominal Power Handling 20 Watts Frequency Response 45 HZ to 30KHz Sensitivity (1W/1m) 90 db Ohm Rating 4 ohm Sold In Pairs