The Anchor Audio PRO-570/1D/6S is a digital wireless intercom system that is easy to configure and easy to operate. The system allows duplex communication by seven users with two master belt pack and five remote belt packs. It has a 500 ft. line of sight range and a built-in Bluetooth capability. The transmitter and receiver operate utilizing in the FCC license free 902-928 MHz range for the U.S. without the need for a base station. The ergonomically designed belt packs have a sturdy XLR headset jack, two heavy duty antennas, headset volume control, microphone gain control, A/B channel selection and PTT or Always On mode. The out of Range LED indicator tells each user when to move closer to the master belt pack.