WITH LIGHT SENSOR -The ultimate automatic door for every chicken breeder The chicken coop door with light sensing system can open the door at dawn and close at dusk through the change of sunlight PERFECT SIZE -The size of the whole automatic chicken door coop is around 13.8''x 9.8'', and the interior door is around 11.8'' x 7.8''. And it's usable for all suitable sized chickens and ducks EASY TO INSTALL -This chicken door works with 3 AA batteries (not included). No complicated wiring , easy to use and convenient to use. Kind Tips: In order to make the chicken coop door work better, do not twist the screws too tightly during the installation process EASY TO USE - Easily programmable pushbutton. It automatically opens in the morning & closes in the evening. You can set the timer or use the integrated (LUX) Light Sensor. WORKS IN EXTREME WEATHER - Waterproof ; will work in snow, rain, and dust from -15F to 140F (-26C to 60C). ALL IN ONE DESIGN - One piece; full aluminum doors and slider. High-quality powder-coated Fine structural color (explicitly designed for the external environment).