Not all picture frames are required to hang on a wall. Often we want them to sit on a table, desk, shelf or some other item of furniture. So instead of placing hanging attachments behind a frame we will create a stand back for the frame as illustrated in the photo below
The brass leg at the bottom of the frame helps it to stand. This leg can also be removed if the picture has to be packed, say if moving house. It can easily be reinserted into the bracket at the bottom of the picture frame. The two photos below show both the brass bracket at the bottom of the frame and the brass leg removed from the bracket.