... 2.8 inch LCD ScreenElegant appearance,multi-colors are availableConvenient operation,simple installation,no wiringDigital audio,voice clearlyIndoor unit monitor outside, ... Alkaline batterOutdoor unit:High resolution 300K pixelsDisplay:2.8 inch LCD screenOutdoor unit angle:105 degreesOperating Temperature:-10 degrees Celsius ... 95%Dimensions:Indoor unit: 108*96*16(mm) 2.8 inch LCD Screen Door Viewer