Screw and Bolt Thread Size Reference
Look up UNC UNF and metric screw and bolt thread sizes with diameter and pitch details.
Standard UNC/UNF machine screw and bolt sizes with major diameter and threads per inch, plus common metric equivalents.
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Screw and Bolt Thread Size Reference is a single-purpose utility on instant.tw, a free toolbox of calculators, converters, generators, and quick lookups. Everything works in your browser — nothing is uploaded, nothing is stored on a server unless explicitly noted.
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