Battery powered from 9volt PP3
Long
battery life (in excess of 100 hours)
Power
on switch
Power
on LED
Low
battery indication
3
user selectable modes:1. 4 wire (for standard connection to other broadcast eqpt)
2. Interrupt loop through (IFB) for monitoring & adding talkback over incoming audio
3. 2 – wire conference mode for connecting multiple GS-FW021 together
2 –
wire mode compatible with prospect C1B
Headset connection on 3 pole 6.35mm (A/B gauge)
Push
to talk button for mic input
Limiter circuit for mic input
Headphone volume control
Auxiliary audio input (on 3.5mm jack) fed to headphone circuit
Transformer balanced 4 wire input/ output
Maximum dimensions just 152 x 42 x 72mm (l x w x d) 
