Windows that are tilted open can be very dangerous for cats because they can get pinched or injured this fencing closes off dangerous openings and is designed so that cats cant climb up it can be screwed or taped on to secure the window from all sides if possible the fencing should be mounted on the window frame with the included screws this guarantees a long lasting secure protection for your cat if it is not possible to screw the fencing on it can also be adhered or taped for example