Pet Doors

Both complex and simple pet doors are manufactured. The simplest are just weighted flaps that allow easy access for your pet. The downside to these pet doors is that they often allow other animals in, as well as the wind, rain, and snow.

Other pet doors have been designed with magnets to hold the door closed. These have advanced to having an electromagnet latch that only opens for magnets worn on your pet's collar. This allows for one-way access through the pet door.

The first pet door, the cat flap, was invented by Sir Isaac Newton. It would seem that Newton, busy contemplating universal theories, didn't want to be bothered to let his cat out. The first pet door arrived in the 17th century and has been in use ever since.

Let your cat in out of the rain - read the articles below to learn more about pet doors.