Pet Screen Door, For Pets Up To 30 LB, Swinging Wire Mesh Door Snaps Directly Onto Your Existing Screen Door Or Window For Quick & Easy Installation, High Impact Plastic Frame Includes A Slide Lock That Will Allow You To Control Your Pals Access, Flap Opening 8" x 9-1/4", Outer Frame Size 9-7/16" x 11-7/16".