ART Phantom II Pro, 2-Channel Phantom power, Battery powered, Supplies up to two condenser microphones with 48V phantom power, Noise and distortion-free circuit, XLR connectors for balanced inputs and outputs, Highly efficient, economical CMOS circuit for long battery life with a standard 9-Volt battery (alkaline recommended), Illuminated on / off switch, Power supply via optional external power supply possible (7.5-12 V DC or AC voltage), Sturdy aluminum housing