Wall plug

A wall plug (UK English) or screw anchor (US English), commonly called a "rawl plug" or dowel in British or US English respectively, is a fiber or plastic (originally wood) dowel used to enable the attachment of a screw in material that is porous or brittle or that would otherwise not support the weight of the object attached with the screw. It is a type of fastener that for example allows screws to be fitted into masonry walls.