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https://writeablog.net/plierwi....ne2/cat-flap-fitting
https://articlescad.com/cat-fl....ap-installation-cost
uPVC door panels offer a long-term solution to composite doors. They are durable, effective and resistant to fire. They are also reasonably priced and easy-to-maintain. Ordering a double-glazed sealed unit that has an opening already cut for the cat flap is the easiest way to install the cat flap on a uPVC sheet. This is a lot safer than trying to cut a hole in an existing glass panel. UPVC Doors are easy to maintain