We definitely need one of these four our home. We do have a feral that escaped after quarantine…Blake. He’s been chipped and although he’s feral, he got along well with our other cats, especially David who is also feral. But Blake, like David never warmed up to humans. So he escaped. We fed him for weeks then suddenly he stopped coming for feedings, and a neighborhood raccoon came to eat his food instead. We tried setting up a safe trap, but it went off prematurely and scared him off. I tell all those details because feral cats really have a tough life out there, so I’m wondering if this door can be programmed without the actual pet chip available, if the number can be entered manually. Maybe one day Blake will return. We love the fact that this product is modular, has good battery life and works with most chips…and has an rfid tag. Shop Now on Trendsetic.com