The Kenwood MC-60A features UP-DOWN tuning (on compatible Kenwood transceivers) plus a built-in pre-amp. There is a switch for PTT (push to talk) and also a lock feature. The mic impedance may be set for 50K ohms or 500 ohms. The frequency response is 150 Hz to 10 kHz (-6dB) with the Preamp off and 200 Hz to 7 kHz (-6 dB) with the Preamp on. The heavy zinc die-cast base provides extra stability. The mic terminates to a standard 8 pin mic plug. The preamp requires two AA cells which are mounted through the bottom of the base. Please note that on some later Kenwood models, such as the TS-2000, it is better to not to use the preamp function (leave switched 'off' and do not install AA cells).