Double channels design, can use two handheld wireless microphones without interference at the same time. - High precision quartz crystal to lock the frequency. - High sensitivity and high S/N ratio, high fidelity without noise. - Superior selectivity, multi-channel can use at the same time, do not interfere with each other. - Suitable for studio / karaoke / radio / etc. - Ideal environment for using distance is up to 50 meters, complex environment and practical distance is 30 - 40 meters.