Small Plexidor Pet door (Loughborough LE11)

This is heavy duty anodised aluminium frame with shatter resistant plexiglad panel. I bought it originally to act as a cat door as it has good draught proofing. But I got a new back door in the end that came with a cat flap so I didn't use it. However, it may be more suited as a dog door due to its strength. They say it can be fitted to UPVC doors and I have instructions but maybe it would be better fitted in wood or brick. The instructions and installation template are included. The outer dimensions are about 25 cm square. The inner dimensions of the opening hole are 165 mm (width) x 184 mm (height). The website is www.dogdoors.co.uk. It's 45 mm thick so thicker than most UPVC doors so the instructions say the overlap needs to go inside of door to retain weatherproofing. See the 4 photos.