Multi-channel wireless instrument set. 30MHz selectable bandwidth. The PT 45 pocket transmitter is compatible with all AKG micro mics and provides up to 8 hours operation from a single (supplied) AA battery, gain control and noiseless on/off/mute switch. SR45 receiver as above. Instrument cable and UK power supply. Band D operates on licence-free channel 70 (ISM) frequencies. Band U systems operate on channel 38.