Abstract: The invention relates to a prefabricated movement joint system with top edge rails providing protection for the concrete floor slab edges. The top edge rails may have a plurality of anchors to embed in the concrete and position the system, which are formed from the parent steel of the rail and not for example welded on. When the top edge rails are joined back to back with the possible use of yieldable fixings they clamp and hold in position possible a nylon or other plastic shaped extrusion and the divider plate thus comprising the whole of the assembled system.