ISO 273:1979 Preview
Fasteners -- Clearance holes for bolts and screws
This standard was last reviewed and confirmed in 2019. Therefore this version remains current.
Specifies diameters for general purpose applications; tabulates the hole diameters for fine, medium and coarse series for thread diameters from 1 mm up to 150 mm; holes for special applications should be selected on the basis of design requirements.
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