Large, Electronic SmartDoor for pets 7-100lbs. Can be installed in panel doors, wood, PVC & metal doors 1-1/2" to 2" thick. Walls and alternative applications may require conversion kit, sold separately. SmartDoor has 3 programmable modes. Automatic mode allows entry and exit for a pet wearing a programmed SmartKey. Locked mode does not allow any pet through. Unlocked mode allows all pets in and out.