3/8" X 1-3/8" NATURAL PINE STOP

In door trim, a stop is attached to the door jamb on both sides and at the top. It is where the door comes to a rest when it is closed, stopping the door from moving any further and covering the gap that would otherwise appear between the door and the jamb. In window trim, a stop holds the bottom sash of a double-hung window in place and can also be used as an apron under window stools.