Cat flaps
Every price here was read on a UK store page, and says which and when. Price per 1,000 kcal appears only where calories are published. The exception is dry cat food, where the figure says what it assumes.
PetSafe Microchip Cat Flap White
Multi-cat homes, up to 40 pets
£70
SureFlap Microchip Cat Flap White, small/medium
Keeping neighbourhood cats out
£70