Cat flap - help!

[Vegboxwonder]

We currently have a manual cat flap, fitted to a UPV external door. The door cut out size for the current cat flap is 150mmWx245mmH. We need to replace it with a microchip operated flap as we're getting a kitten, who will need to stay in for several months, and existing DCat is used to coming and going as he pleases.
All the microchip flaps I can find require a much smaller cut out! Has anyone found one that matches the dimensions above? Or is there some magic solution I haven't thought of?! All help very gratefully received!

I swapped out a large flap (for previous giant cat) to a small microchip flap for current little cat and used one of these to reduce the space:

https://www.petsathome.com/product/sureflap-microchip-cat-flap-connect-mounting-adaptor-white/7118152P?productId=7118152&purchaseType=one-time&size=oneSize

If that doesn't work, it's not hard or expensive to have a new panel cut for the door (assuming it's a standard uPVC door).

Thank you. I've ordered an adaptor - fingers crossed!

Thank you so much! The adaptor did the job with only two tiny gaps at the top corners of the old hole, which were easy to make good 🙂 We're now all set for arrival of DKitten!

You’re probably already aware of this but the microchip will normally only stop cats coming in, not going out. So you may have to install the new cat flap back to front

If it's the Sureflap microchip connect with the hub then it's a smart flap and can be set for different chips to do different things.
We have just got one for our kittens who will be going out in a few weeks.

It's the sure flap dual scan, so scans both ways

Excellent. Yes, mine wasn't a perfect fit but some caulk sorted it!