The BP-9000M from Anchor Audio/PortaCom is a master beltpack for use as part of a ProLink intercom system. The beltpack features a compact and portable design, and offers full-duplex communication without the need for a base station. It can support up to 3 remote beltpacks for clear communication at distances up to 250' away. The master beltpack has an LED indicator that flashes red when it is transmitting to a remote beltpack.The BP-9000M has an A/B channel selector, a power/volume knob, and a mic gain control to precisely adjust the operation to meet your needs. A push-to-talk button lets you communicate at will, while the "always on" slide switch lets you talk freely without using the PTT button. The beltpack has a 4-pin XLR headset connector for use with Anchor Audio headsets, or any headset with a dynamic microphone. The beltpack operates on a set of 3 AA rechargeable batteries and has a charging port for quick charging in a gang charger.