Boytone BT-54UM Built-in High-quality Capsule and chip and advanced digital decoding technology to reproduce more excellent, clear, pure and full sound. Built-in LNA line ensures less background noise and howling in microphone. High grade crystal oscillator is adopted to ensure accurate frequency adjustment and stable signal transferring for uninterrupted signal. The range is up to (196 to 260 FT) in open space. Durable Material Metal: 2 wireless microphone and base with steel mesh grille is particularly resistant to impact and corrosion. The receiver and wireless microphone is designed with a LCD display screen, all information is clearly at a glance. Easy to Operate System: Wireless microphone and receiver frequency set by manufacturer, no other operation is needed. 2 x AA batteries (included) are required for each mic. Package included: Receiver,2 microphone transmitter, power adapter (110-240Volt), 1/4 audio cable, 2 Antenna, 2 different color of microphone foam, 4 AA batter