Pre-Tapping Hole Sizes

ISO Metric Threads Coarse PitchISOMetric Threads FinePitchISOMetric Threads Fine Pitch
MPitch mmMax Core Dia.mmDrill Size mmMFPitch mmMax Core Dia.mmDrill Size mmMFPitch mmMax Core Dia.mmDrill Size mm
10.250.7850.752.50.352.2212.15252.0023.21023.00
1.10.250.8850.8530.352.2712.65261.5024.67624.50
1.20.250.9850.953.50.353.2213.15271.0026.15326.00
1.40.301.1601.1040.503.5993.50271.5025.67625.50
1.60.351.3211.254.50.504.0994.00272.0025.21025.00
1.70.351.3461.3050.504.5994.50281.0027.15327.00
1.80.351.5211.455.50.505.0995.00281.5026.67626.50
20.401.6791.6060.755.3785.20282.0026.21026.00
2.20.451.8381.7570.756.3786.20301.0029.15329.00
2.30.401.9201.9080.757.3787.20301.5028.67628.50
2.50.452.1382.0581.007.1537.00302.0028.21028.00
2.60.452.1762.1090.758.3788.20303.0027.25227.00
30.502.5992.5091.008.1538.00321.5030.67530.50
3.50.603.0102.90100.759.3789.20322.0030.21030.00
40.703.4223.30101.009.1539.00331.5031.67631.50
4,50.753.8783.70101.258.9128.80332.0031.21031.00
50.804.3344.20110.7510.37810.20333.0030.25230.00
61.005.1535.00111.0010.15310.00351.5033.67633.50
71.006.1536.00121.0011.15311.00361.5034.67634.50
81.256.9126.80121,2510.91210.80362.0034.21034.00
91,257.9127.80121,5010.67610.50363.0033.25233.00
101.508.6768.50141,0013.15313.00381.5036.67636.50
111.509.6769.50141,2512.91212.80391.5037.67637.50
121.7510.44110.20141.5012.67612.50392.0037.21037.00
142.0012.21012.00151.0014.15314.00393.0036.25236.00
162.0014.21014.00151.5013.67613.50401,5038.67638.50
182.5015.74415.50161.0015.15315.00402.0038.21038.00
202.5017.74417.50161.5014.67614.50403,0037.25237.00
222.5019.74419.50171.0016.15316.00421,5040.67640.50
243.0021.25221.00171.5015.67615.50422,0040.21040.00
273.0024.25224.00181.0017.15317.00423,0039.25239.00
303.5026.77126.50181.5016.67616.50451.5043.67643.50
333.5029.77129.50182.0016.21016.00452.0043.21043.00
364.0032.27032.00201.0019.15319.00453.0042.25242.00
394.0035.27035.00201.5018.67618.50481.5046.67646.50
424.5037.79937.50202.0018.21018.00482.0046.21046.00
454.5040.79940.50221,0021.15321.00483.0045.25245.00
485.0043.29743.00221.5020.67620.50501.5048.67648.50
525.0047.29747.00222.0020.21020.00502.0048.21048.00
565.5050.79650.50241.0023.15323.00503.0047.25247.00
605.5054.79654.50241,5022.67622.50521.5050.67650.50
646.0058.30558.00242,0022.21022.00522.0050.21050.00
686.0062.30562.00251.0024.15324.00523.0049.25249.00
251.5023.67623.50