DESC: Adjusts to fit openings between 76 3/4" x 81" (prior to purchasing a panel, determine height of your sliding glass door frame opening. Measure from the highest point in upper track to lowest point in lower track) Heavy-duty aluminum construction with a super-hard powder coat finish that will not corrode Installs in left or right closing/sliding doors - has reversible lock Energy conserving UltraSeal® flap Insulated and locking closing panel, Weight: 20 lbs., Manufacturer: PetSafe