Megapixel: With a professional security camera, you can restore picture details better, giving you a great visual experience. 120 Wide-angle Lens: Equipped with a 120 wide-angle lens, clear into the details outside the door to reduce hazards. Fashionable design: Fashionable and classic design, simple features, it is suitable for European and American aesthetics. Invisible camera: Using invisible camera with a similar appearance to the traditional peephole,with one-click viewing without storage to protect privacy. Zinc alloy outdoor sub-machine: Zinc alloy material is -proof, it can prevent human damage to the maximum extent. Type: Peephole Doorbell Sensor: 2 CMOS Sensor Screen Size: 3.5-inch LCD Screen Function: Energy Saving, Low Power Alert Power Supply: 4 x AAA Batteries (Not Included). Outdoor Parts Size: Diameter 31mm Door Hole Range: 14-28mm Door Thickness Range: 35-110mm Note: 1. Please confirm the power of the AAA battery before use, it is best to use a new battery. Please confirm the positive and negative poles of the battery during installation. 2.This doorbell is simply peephole doorbell. You cannot link your mobile phone and WiFi. The outdoor machine does not have a button. Please choose as needed!!! 3. First install the battery, then connect the lines, and finally start the test and use it. Colour:black Material:Zinc alloy Size:120x62x20mm Package Contents: 1 x Indoor host 1 x Outdoor cat's eye host 1 x Metal hanging board 1 set x screws Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.