SPKR 4/AMP UPGRDE KT 11-13RG U Includes pair of 7 1/4in. round driver, the largest diameter speakers that can be installed into the HarleyRoadGlide style fairing and vented lower fairings, with cone volume and mass comparable to a 6in. x 9in. speaker Includes pair of 5 1/4in. round drivers, the largest and most efficient speakers you can install into the rear trunk pod position on the Harley RoadGlide Ultra Both speced at 2 ohms impedance and 140/120+ watts max power, these new speakers provide the ultimate in bass response, extended mid/high frequency range and raw audio power Features a waterproof injection-molded polycarbonate woofer cone, high-flux strength but lightweight dual-donut Neodymium magnet, high efficiency voice coil, the latest design grillwork with mounted tweeter and midrange, (plain grills only for LOWER fairing speakers) and top-quality adapter rings/bracket hardware for secure and clean mounting Full range class D amplifier and is speced at 90 watts RMS per channel X4 channels, (360w total) driven continuous into a 2 ohm load at 14.4vdc.