https://wifidb.science/wiki/Through_Wall_Cat_Flap
If you want to install a cat flap in your home, it's recommended to employ an expert tradesperson. DIY projects typically result in poorly fitted pet flaps that allow in drafts and cause more energy costs. SheffLOCK can fit the cat flap into all kinds of doors like wood composite, uPVC, composite, glass doors, as well as external walls. On average, it takes about two hours to install a cat flap. Pet flaps cost money A pet flap permits your cat to go and come whenever it wants. If the flap is not installed correctly, it could allow heat