Having had problems with a "visitor" night marking in our home and attacked our cats, this solution is absolutely brilliant. Quick and easy installation, this flap has changed our lives. Practice also be able to close the system to prevent our cats to go out or when there is need. Occasionally an old nail comes in the door, causing some inconvenience on waking when cats were unable to relieve themselves outside (it happened once), otherwise than that, independent of the function of product, nothing negative to point out. Even the cold can not fit through this conduit.
