SecurityMan SM-8209R Add-on wireless receiver/ monitor of PalmWatch III w/2.4" LCD (900MHz) Compatible with other SecurityMan 900MHz cameras Portable and battery operable monitor(2.4 TFT- LCD) Microphone built-in to camera, and speaker built-in to receiver Two channels receiver supports up to two cameras (2CH:906MHZ & 924MHz) Battery Working Time: 5 hours (4xAA)