I'm in the process of building a set for my theatre and was looking for a certain type of locks to keep a set piece in place during scenes. It is a simple four step stair piece that is on castors. The last large production we did was Beauty and the Beast and we rented the set from Gateway Playhouse, and on some of the set pieces they had the locks that I was looking for. They attached to the side of the set piece and had a steel rod that plunged downward into the stage controlled by a small lever. Hope this was enough info for you all to get an idea to what I need! Much thanks.