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 the 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 models Swing 1, 3, or 5. An important feature is the 4-way locking system (not included in the Swing 1 model), which allows you to customize 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 that simultaneously indicates the direction in which your furry friend last moved. All larger flaps come 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 are 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.