1.Wide view angle：165 degree 2.Low power consumption: 4 AAA Batteries can be used for more than 3 years 3.Clean and big image:0.3 Mega Pixel CMOS sensor,3.5inch LCD 4.Easy assemble: no wires, no damage on the door, no tools 5.Thickness: only 16mm Fits door: 40-70,70-110mm (1.58"-4.32") Fits barrel hole: 14-25mm 3.5 inch:TFT LCD Sensor: 0.3Mega Pixel Viewing Angle: 165 Degrees(D) /120 (H) Power Source:4 AA batteries Product Size: 126*79*16.8mm Color: silver,gold or customized