The system is supplied with amplifier, piezo electric transducer, headset and carrying pouch. Amplifier has input jack for transducer and output jack for headset or recorder. Output impedance of 16 to 2000 ohms can match virtually any headset. The 4020 is powered by a single 9 volt battery which, under normal conditions, provides over 200 hours of operating life.
Amplifier contains belt clip for easy mounting.