Pride Pet Doors are constructed with a strong extruded frame. The flaps are made of flexible heavy duty rubber that will not crack in winter or warp in summer. Magnets are imbedded into the durable rubber flaps to help keep the flap closed and eliminate drafts. The SD300 is for cats and small dogs. The opening is 4 3/4 inches x 7 1/2 inches, for your pet up to 4 1/2 inches across the shoulder. The pet door should be one half inch wider than the width of the pet’s shoulder.
