Old staywell cat flap (Shipley, BD18)

I have an old Staywell cat flap if it is any good to anybody, we took it out about 8 yr ago to fit an electronic one when we had another cat visiting ! It does work fine and comes with a spare door, it is very diiscoloured on the outside. It would maybe do for use on a shed door for the winter to give a cat some shelter, or maybe could be put on a home made kennel / cat shelter. Can be fit in glass too.