I recently came across this wonderful product - it's a microchip cat flap!
This cat flap works with your cats existing microchip so no collar is necessary.
Lets your cat in and keeps other cats out.
Protects your home from spraying, damage to furniture, and stray cats coming in and stealing food while you're out.
I think this is wonderful because I have always wanted to get a cat flap for my two kitties, but I don't want them to have to wear collars.
This cat flap is the answer - it can be fitted in glass as well as wood and UPVC. There is also a wall version.
You can program up to 12 cats into the system.
The Day and Night Sensor is useful if you are concerned about your cats being out at night, but if you live in an area where your cats are safe to be out and about at night, you can leave the cat flap unlocked.
Hope this is useful,
Candy
Microchip Cat Flaps
Cat Flap 
Linear Mode
