Royal 29297W WES 600 Wireless Stereo Speaker System Auto scanning and 2-way system Bass/Boost selection Magnetic shielded speakers No line of sight limitation Virtual interference-free audio quality Auto on/off control and Auto tuning function UHF stereo transmission mode Operation distance up to 164 feet Automatic PLL on transmitter and speaker RF technology lets you roam freely throughout your house or yard DC 12.5V 150mA power adapter