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

Fixing the V shape is what lets any matching nut fit any bolt. The figure is taken from International Organization for Standardization, 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.

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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

Metric threads all share a sixty degree angle

Fixing the V shape is what lets any matching nut fit any bolt ISO metric threads have a 60 degree included angle and are described by nominal diameter and pitch, so an M8 bolt is about 8 millimetres across with a standard pitch of 1.25 millimetres. A shared angle makes parts interchangeable between countries and factories. Older inch threads used 55 degrees, which is why the two systems do not mate. It sits in Mondo's everyday life collection, one of 200 facts that each trace back to the reference below.

Where this comes from

International Organization for Standardization

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: engineering, threads, standards

Metric threads all share a sixty degree angle: the short answers

Where does this come from, and can I check it?: Fixing the V shape is what lets any matching nut fit any bolt. The figure is taken from International Organization for Standardization, 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.