High Tech Pet - Large Power Pet Sliding Glass Door for Dogs and Cats - Shorty Turns any sliding glass door into a fully automatic pet door pet door insert easily fits into your sliding glass patio door track Motor driven vertically-sliding door is activated by MS-4 ultrasonic collar Directional sensing system opens the door only when your pet is on a direct approach, not when he is just wandering by or sleeping next to the door 4-Way access control lets you select from In only, out only, Full Access or closed and locked Height range is 75 to 77-1/2-inch 14-inch wide panel size: 12-1/4 X 16-inch for pets up to 100-pound