Metric wire: (from Renner catalogue) size mm inches 13 0.775 0.0305 13.5 0.800 0.0315 14 0.825 0.0325 14.5 0.850 0.0335 15 0.875 0.0345 15.5 0.900 0.0354 16 0.925 0.0364 16.5 0.950 0.0374 17 0.975 0.0384 17.5 1.000 0.0394 18 1.025 0.0404 18.5 1.050 0.0413 19 1.075 0.0423 19.5 1.100 0.0433 20 1.125 0.0443 20.5 1.150 0.0453 21 1.175 0.0463 Hope this helps. Jerry Anderson
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