Monoprice 12 Inch 150 Watt Powered Subwoofer, Black (109723) 12" High Performance Powered Subwoofer 150 Watts RMS, 200 Watts Peak 50 ~ 250 Hz Frequency Response The internal battery has an operating life of approximately 9 hours giving you a full day of audio bliss This small device is designed to transmit audio to up to two sets of Bluetooth receivers usually headphones The splitter has an operating range of up to about 30 feet (10 meters)