Wires for UN threads

The nominal diameters of best-size wires and the allocation of number of threads per 25,4 mm (1 inch) are given in the table.

Nominal diameter
of wires
mm		 Threads per
25,4 mm		 Nominal diameter
 of wires
mm		 Threads per
25,4 mm
0.183 80 0.917 16
0.204 72 1.047 14
0.229 64 1.128 13
0.262 56 1.222 12
0.306 48 1.275 11.5
0.333 44 1.333 11
0.367 40 1.466 10
0.407 36 1.629 9
0.458 32 1.833 8
0.524 28 2.095 7
0.543 27 2.444 6
0.611 24 2.933 5
0.733 20 3.259 4.5
0.815 18 3.666 4
 

Supplements:

Reference:

  • ISO 16239:2013 Metric series wires for measuring screw threads