1. The product is installed within the position of the peephole at the door, replacing the optical peephole door mirror, and obviously displays the image outside the door on the screen of the host inside the door, permitting the owner to look the guests outdoors the door at home, and manually take pictures. 2. The outside mechanical device replaces the ancient optical cat eye, doesn't need to look closely, has a large visual range, isn't restricted through height, and can be appropriate for the elderly and children. 3. Zinc alloy material outdoors the door (anti-theft, anti-pry, anti-peeping). 4. The outdoors unit has a integrated camera, the appearance has similarities to the traditional cat's eye (CMOS 1 million pixels, most support 1280*720P, display/record outdoor images) 5. The in-door machine makes use of a 4.3-inch TFT LCD exhibit 6. The host adopts single button operation, simple operation and practical function. Parameter: The diameter of the mini hidden cathead is 35mm (generally about 65mm) Horizontal viewing angle: one hundred forty five degrees Automatic shutdown: 15 seconds Power-off memory: support Standby current: 100UA Working temperature and humidity: -30Celsius-65Celsius(outdoor)/ -10Celsius-50Celsius(indoor) humidity is less than 90% Installation method: screw putting plate Battery: 3.7V 1800MA lithium battery, 1 common Colour:black Material:Zinc alloySupport door thickness 35-110MMDisplay screen size: one hundred thirty * 85 * 12mm Package Contents: 1 * indoor observer 1 * peephole digital camera 1 * hanging board 6 * screws 1 * English person manual Only the above equipment content, other products are usually not included. Note: Light taking pictures and various displays could cause the colour of the thing within the photograph just a little various from the genuine thing. The dimension allowed error is +/- 1-3cm.Support door thickness: 35-110MMSupport door gap size: 15-25mm