Features a durable metal gear used to lift the door. Includes waterproof con-troller (works in rain and snow). Choose between light sensor or timer to open and close the door, allowing you to pick the one that best suits your needs. No need to worry about your chicken not moving in time while the door is closing, because the motor will automatically stop If your chicken is in the way. This unit is battery powered by 4 AA alkaline batteries. Batteries not included. Some assembly required.