The wall systems can be mounted on a sloping wall. The rail is installed in just the same way it would be on a straight wall. The hanging rail must be positioned in such a way that the rail itself doesn’t slide down. You should use a Stopper Set to hang frames/pictures on a sloping wall.  This Stopper Set will keep the hanging wire in the right place, and the wall decoration will hang straight. The stopper locks the hanging wire by tightening the socket head screw in the stopper. The stopper will always be positioned lower than the hanging wire. When mounting a picture hanging system on a sloping wall, we advise that you use Solid Slider hanging wires. When using a Stopper Set, the maximum weight of a frame is 4 kg.