ESB HR 11 SW Harmony Series 11 Inch Car Spare Wheel Active Subwoofer 200w RMSHR 11 SW 11" 260 mm Active Spare Tyre Subwoofer The HR 11 SW is an active subwoofer that fits inside the rim of the spare tyre! Its die cast aluminum case makes it sturdy and long lasting. Easy to install, the HR 11 SW provides a powerful and dynamic sound thanks to a dual voice coil speaker and a 200 Watt Class D digital amplifier. With the included remote control, the user can adjust the volume level, changes the phase (non inverted or inverted),