Unique self-adjusting design for an easy installation with no cutting required. Soft transparent all weather, energy conserving flap system reduces energy loss in winter and summer. Locking security cover may be installed on either side of the door. Adjustable height for 76 3/4 In. to 81 In. for regular patio doors and 93 In. to 96 In. for tall patio doors. Reversible lock for right or left sliding doors. Shatter resistant Tempered safety glass.