... - Unlock Door, View Monitor. Talk Button, MIC, LED Indicator, Mini USB Input, Speaker, Volume -/+, Brightness control -/+, Antenna, Power ON/OFF Switch , Work ... - Transmitting Frequency - 2.4GHz -- Onboard Buttons/Indicators -Microphone, Call button , Speaker, USB interface for charge , Power switch , ‘Pairing’ button, Indicating light ...