Features: 48V phantom power supply for the signal condenser microphone, stable and reliable. Built-in low pass filter circuit design can filter out interference noise; stable voltage doubler-rectifier can effectively filter out the signal interference. With the balanced XLR input output jacks to connect in-line with your condenser mic and mixer. USB-powered operation, compact size and full metal shell, portable and durable. With on-off switch and LED indicator for easy and safe operation.