Automatic, Non-Handed, Reversible Ideal for Use With Carpeted Interiors Commercial Medium-Duty Automatic Door Bottom is a mechanically actuated door bottom. An internal carrier bar with a vinyl insert drops from a concealed cavity to form a tight seal between the base of the door and the threshold preventing dust, moisture and wind from entering. It is ideal for use where carpeted interiors require the door bottom to retract when the door is opened. Pemko Automatic Door Bottoms consist of an aluminum case which surrounds a movable drop bar seal. The drop bar seal is actuated by a plunger which contacts the jamb as the door is closing, forcing the drop bar seal down against the floor or threshold. Automatic Door bottoms are frequently used when an automatic door bottom is required to close over carpet. Pemko Automatic Door Bottoms provides low closing force and excellent seals to keep out draft, dust, moisture, insects, fumes, light and sound. Supplied with a frame "actuator" protector plate, the door bottom is field reversible for either "hand" of door, and may be field cut to a maximum of two inches (50.8) millimeters. Cut from end opposite actuating plunger only. Color: Aluminum Finish Length: 42 in It is sized for a 42 in opening with an overall size of 42-1/2 in Installation Instructions