STIMME MC-PG24 ,WIRELESS MICROPHONE , PRO AUDIO, 600 ohm, CARRYING CASE, 1/4 MICROPHONE FEATURES:DYNAMIC UNIDIRECTIONAL, 600ohm, RF POWER OUTPUT: &lt;30mW, GAIN CONTROL ON THE MICROPHONE, 9V BATTERY OPERATION, BATTERY LIFE: OVER 8 HOURS CONTINUOUS OPERATION, PWR ON/OFF SWITCH, ON/MUTE SWITCH ( NO POPPING), ANTI- INTERFERENCE MODULAR DESIGN