Citroen C4 Grand Picasso fitting a sub woofer and tweeters. - YouTube
6.5 Inch Dance Active Subwoofer Car Audio 100W 4ohm 220V 5V Built-in Li Battery 3.7V with Bluetooth USB/TF Card/Aux/FM Radio/Microphone LED Light Speaker Box - China Active Speaker and 5 Inch Subwoofer