Ferplast Cat Doors Swing 5 Tunnel, 4-Way Cat Door for Cats and Small Dogs. With tunnel; last passage indicator in/out; door closes gently. Dimensions: 22.5 x 9.6 x 25.2 cm. Thanks to Ferplast Swing products, you can install the flap exclusively for your four-legged friend on any wooden, metal, or glass door as well as on brick walls. For cats and puppies, we recommend the Swing 1, 3, or 5 models. An important feature is the 4-way locking system (not included in the Swing 1 model), which allows you to adjust the type of opening to your needs: entry only, exit only, both entry and exit, or closed. The passage indicator (in the Swing 5 model) shows whether your pet is inside or outside the house. It consists of a flag attached to the bottom of the cat flap, indicating the direction in which your furry friend last moved. All larger flaps are equipped with a tunnel, allowing the flap to be installed on any structure. For the Swing 5 model and the Swing 1 and 3 models for smaller pets, a new modular tunnel extension is available as an accessory. This extends 5 cm in depth (screws not included). We recommend consulting a glazier before installation in glass constructions, as it is not possible to drill holes in safety glass or double glazing. Universally suitable for all materials.