- High quality material: The PET flap is made of ABS material with a smooth surface, offering strength and reliable quality assurance. - PET cat and dog flap sizes: Available in 3 sizes; choose according to your pet size. - Large: outer size 25 x 23.5 x 5.5 cm (H x W x D); inner size 19 x 18 cm (H x W) - Medium: outer size 20 x 19.2 x 5.5 cm (H x W XD); inner size 15.5 x 14.7 cm (H x W) - Small: outer size 20 x 19.2 x 1.8 cm (H x W x D); inner size 15.5 x 14.7 cm (H x W) - 4 way lock: The cat door features 4 switching modes. It can be adjusted using labeled red and green switches. It can be set to a single mode or completely locked, making it easy to keep your pets in or out while allowing flexibility for your cat or a small dog to come and go without disturbance. - Thoughtful design and visibility: The transparent flip cover lets your pet see through the door. The outer screen is waterproof. A brush strip reduces noise from door closing, helping prevent disturbance to pets and owners.