Milky White Plastic PVC Roll Plug, For Industrial Use

There are many forms of wall plug, but the most common principle is to use a tapered tube of soft material, such as plastic. This is inserted loosely into a drilled hole, then a screw is tightened into the centre. As the screw enters the plug, the soft material of the plug expands conforming tightly to the wall material. Such anchors can attach one object to another in situations where screws, nails, adhesives, or other simple  are either impractical or ineffective. Different types have different levels of strength and can be used on different types of surfaces.