This bundle contains two pairs of Kicker 44KSC404 4" speakers KS Series 4" Coax The KSC Four Inch Coaxial Speakers delivers the smooth, accurate audio you've been craving. Features: High Power Handling Extended Dynamic Range Silk Dome Tweeters For A Smooth Sound Polypropylene Woofer And Tough Rubber Surrounds Thin-Mount Design Easily Fits Behind Factory Grilles Grilles Included These KSC speakers work best with 75 watts of recommended power. See below for more details. Specifications Speaker Design 2-Way Woofer [in, mm] 4, 100 Mid [in, mm] Not Applicable Tweeter [in,mm] ½, 13 Rated Impedance [Ω] 4 Peak Power Handling [Watts] 150 Continuous Power Handling [Watts RMS] 75 Sensitivity [1W, 1m] 88 Frequency Response [Hz] 60-20k Mounting Hole Diameter [in, mm] 3-11⁄16 , 94 Top Mount Depth [in, mm] 1-13⁄16 , 46 Bottom Mount Depth [in, mm] 2-1⁄16, 51 Tweeter Protrusion [in,mm] 0 Grilles yes Tweeter Magnet Material Neodymium Tweeter Dome Material Silk Tweeter Design Balanced Dome Woofer Cone Material Polypropylene Woofer Surround Material Rubber