The Whirlwind Isopod Stereo TRS to Mono XLR Balancer is an in-line device for iPods, portable MP3 players, laptop audio outputs, and more. The Isopod converts the stereo signal from your player/device to a balanced summed-mono audio signal for XLR line inputs on audio consoles, recorders, and more. The Isopod is simple to use and features a stereo 3.5mm input and mono-balanced XLR line output.