These Forgefix plastic Expansion Wall Plugs are an extremely popular all-purpose lightweight fixing. They are colour-coded for size. The anti-rotation moulding at the head of the plug improves the holding power when inserted. It provides a cost effective solution for lightweight fixing applications. When a screw is inserted, the screwing action wedges the plug firmly in place, the soft material conforming tightly to the wall. The wall plugs are suitable for most types of threaded screws, including multi-purpose, general purpose, coach screws etc. Not suitable for Machine Screw threads.