The Dolphin SPF-28R is WaveSync™ enabled, wirelessly pair two speakers and play music through Bluetooth, this speaker is also accessorized with a remote control and a wireless microphone. With Dual 8 inch woofers and a 1.5 inch tweeter, and 40 RMS of music power, the main channel inputs are – Bluetooth, USB Drive, Mp3 Player, Micro SD Card Mp3 Player, FM Scan Radio and 3.5mm Auxiliary. Channel 2 has one 1/4″ Microphone Jack, Volume and Echo Controls. The 7.4V 4400mAh Lithium-Ion battery gives 5 plus hours of playtime, LED indicator display, and equipped with an 7-Function Fire Light which can be switched on or off. Sound controls for Volume, Treble and Bass.