Where does this come from, and can I check it?

A screw wedges a fibre or plastic sleeve outward against the masonry. The figure is taken from US Patent and Trademark Office, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.

Is this really a everyday life fact?

Yes. It sits on the Everyday Life shelf, one of 2,600 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.

What else can I read about it?

The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.

Mondo Knows Facts

Wall plugs grip by expanding inside a drilled hole

A screw wedges a fibre or plastic sleeve outward against the masonry The plug is a split sleeve slightly wider than the hole, and driving a screw into its tapered throat forces the segments outward into the brick. Friction and the compressed material carry the load, so the fixing holds in masonry that would crumble around a bare screw. John Joseph Rawlings patented an early version in Britain in 1911. It sits in Mondo's everyday life collection, one of 200 facts that each trace back to the reference below.

Where this comes from

US Patent and Trademark Office

Facts that can change over time are reviewed and updated. If something here looks wrong, Mondo would rather know than be confidently incorrect.

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Tags: fixings, building, invention

Wall plugs grip by expanding inside a drilled hole: the short answers

Where does this come from, and can I check it?: A screw wedges a fibre or plastic sleeve outward against the masonry. The figure is taken from US Patent and Trademark Office, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
Is this really a everyday life fact?: Yes. It sits on the Everyday Life shelf, one of 2,600 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.
What else can I read about it?: The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.