GS-FW021 is a battery-powered beltpack for four-wire communication with a headset. It can operate as a four-wire interface, an IFB interrupt loop-through unit or a two-wire conference unit for linking multiple beltpacks.

• Headset connection on a 3-pole 6.35 mm jack.
• Push-To-Talk button for microphone activation.
• Limiter on the microphone input and headphone volume control.
• Auxiliary audio input on 3.5 mm jack routed to the headphone circuit.
• Transformer-balanced four-wire input and output.