Thermo Panel 2e SureFlap Microchip Pet Door Color: White, Size: 74.75" x 77.75" Sureflap has included the usual 4-way lock but, a first, has made it electronic Because the Sureflap reads embedded microchips, your pet doesn't have to wear--and possibly lose-a collar key Your pet can come and go at will. But strays, skunks and even raccoons are not coming in!