... Talk, Take a Picture, Increase Volume Decrease Volume, View Last Picture, View Next Picture, Signal Bar, Battery Bar Power Source: ... 50 meters (ideal conditions) Onboard Buttons/Indicators - Unlock Door, View Monitor. Talk Button, MIC, LED Indicator, Mini USB Input, ... -vision-guardian-wireless-video-door-phone-with-dual-receivers-cmos-sensor/OR>>http://www.chinavasion.com/6y0q/ Double Vision Guardian ...