Description of the external product (L x W x H): 19 x 21.5 x 5.5 cm Internal size (L x W x H): 16 x 15.7 x 5.5 cm It is suitable for cats weighing less than 7 kg and a tower of size less than 40 cm. Note: 1). Make sure the width and height (at the The shoulders) of the animal are lower than the pet mesh for pets, thank you. 2) The magnet at the bottom of the door frame is used to align the shutter after the movements, it does not work like a lock, thank you. Improved product features: & nbsp; 1. Practical button style switch, you can easily control your cat or other cat input or output options, only with your fingertips. the entrance, at the entrance, at the entrance and the entrance. outing, totally locked. & nbsp; 2. Fixed groove with agrave tabs; The pressure of a tie strip resistant help greatly helps to repair it. & nbsp; 3. The depth of the tunnel can be reduced, plus 1 pack of long screws + 1 pack of short screws, double -sided adhesive tape, to meet the needs of the tunnel.