We paid a rather whopping £170 off quid to get two cat flaps and have them fitted as had two doors that needed to be accessed. One is a chip operated the other a bog standard old fashioned flap.
Our ginger tom has gone from a kitten the size of a guinee pig to an almost adult looking cat in just under 5 months. Am now worried he will out grow cat flat! I don't think they make bigger ones and we can't afford it anyway do they just cope??
Two of my cats are hugely fat (I'm so ashamed - I'm such a bad cat mother) but anyway they both manage to get through a standard flap (and really there can't be many cats bigger than them). It's a bit of a squeeze but they manage it