Universal Interior Slide Lock for 2" or 3" Track
slide lock is installed on the garage door section end stile. The slide
part of the lock engages with the vertical garage door track so the
garage door cannot be opened. Can be used on 2" or 3" vertical tracks.
Use one lock for garage doors with torsion springs and two locks (one
mounted on either side of the garage door) for doors with extension
Optional 1/4x3/4 screws can be found here for mounting the interior lock on steel garage doors