Technical Description of productsInformation 14. Tap, Thread Limits ■ for Helical Coil Wire Thread Inserts, Metric Threads Unit:mm ■ for Helical Coil Wire Thread Inserts, Unified Threads Unit:mm MajorDiameterPitch Diameter MinorDiameter MajorDiameterPitch Diameter MinorDiameter Size Class Basic Upper LowerBasicTolerance ToleranceBasic Size Class Basic Upper LowerBasicTolerance ToleranceBasic Size Size ( μ m) ( μ m) Size Size Size ( μ m) ( μ m) Size + + + + STI M 2.6 × 0.45 Ⅰb 3.185 2.892 18 6 2.698 Ⅰb 18 6 STI No. 2 - 56 UNC 2.773 2.479 2.283 Ⅰb 18 6 GH2 25.4 12.7 STI M 3 × 0.5 3.650 3.324 3.108 G3 38 25 Ⅰb 18 6 STI No. 4 - 40 UNC 3.670 3.258 2.981 Ⅰb 18 6 GH2 25.4 12.7 STI M 4 × 0.7 4.909 4.454 4.151 G4 51 38 STI No. 4 - 48 UNF Ⅰb 3.532 3.189 18 6 2.958 Ⅰb 18 6 STI No. 5 - 40 UNC Ⅰb 4.000 3.589 18 6 3.312 STI M 5 × 0.8 6.039 5.519 5.173 G4 51 38 Ⅰb 18 6 STI No. 6 - 32 UNC 4.536 4.021 3.678 Ⅰb 18 6 GH3 38.1 25.4 STI M 6 ×1 7.299 6.649 6.216 G4 51 38 STI No. 6 - 40 UNF Ⅰb 4.330 3.919 18 6 3.642 Ⅰb 18 6 Ⅰb 18 6 STI M 8 × 1.25 9.624 8.812 8.271 STI No. 8 - 32 UNC 5.197 4.681 4.338 G4 51 38 GH3 38.1 25.4 Ⅰb 22 7 STI No. 8 - 36 UNF Ⅰb 5.083 4.625 18 6 4.318 STI M 10 × 1.5 11.948 10.974 10.324 G5 64 51 Ⅰb 18 6 STI No. 10 - 24 UNC 6.201 5.513 5.055 STI M 10 × 1.25 Ⅰb 11.624 10.812 18 6 10.271 GH2 25.4 12.7 STI M 10 × 1 Ⅰb 11.299 10.649 18 6 10.216 Ⅰb 18 6 STI No. 10 - 32 UNF 5.857 5.341 4.998 Ⅰb 22 7 GH2 25.4 12.7 STI M 12 × 1.75 14.273 13.136 12.379 G6 76 64 STI No. 12 - 24 UNC Ⅰb 6.861 6.173 18 6 5.716 STI M 12 × 1.5 Ⅰb 13.948 12.974 21 7 12.324 Ⅰb 22 7 STI 1/4 - 20 UNC 8.000 7.174 6.626 STI M 12 × 1.25 Ⅰb 13.624 12.812 21 7 12.271 GH3 38.1 25.4 STI M 14 × 2 Ⅰb 16.598 15.299 22 7 14.433 Ⅰb 18 6 STI 1/4 - 28 UNF 7.528 6.939 6.545 STI M 14 × 1.5 Ⅰb 15.948 14.974 21 7 14.324 GH2 25.4 12.7 STI M 16 × 2 Ⅰb 18.598 17.299 22 7 16.433 Ⅰb 22 7 STI 5/16 - 18 UNC 9.771 8.854 8.244 STI M 16 × 1.5 Ⅰb 17.948 16.974 21 7 16.324 GH3 38.1 25.4 STI M 18 × 2.5 Ⅰb 21.248 19.624 30 10 18.542 STI 5/16 - 24 UNF Ⅰb 9.313 8.624 18 6 8.167 STI M 18 × 1.5 Ⅰb 19.948 18.974 24 8 18.324 Ⅰb 22 7 STI 3/8 - 16 UNC 11.587 10.556 9.867 STI M 20 × 2.5 Ⅰb 23.248 21.624 30 10 20.542 GH3 38.1 25.4 STI M 20 × 1.5 Ⅰb 21.948 20.974 24 8 20.324 STI 3/8 - 24 UNF Ⅰb 10.900 10.212 18 6 9.754 STI M 22 × 2.5 Ⅰb 25.248 23.624 30 10 22.542 Ⅰb 30 10 STI 7/16 - 14 UNC 13.469 12.291 11.506 STI M 22 × 1.5 Ⅰb 23.948 22.974 24 8 22.324 GH3 38.1 25.4 STI M 24 × 3 Ⅰb 27.897 25.948 30 10 24.649 Ⅰb 18 6 STI 7/16 - 20 UNF 12.762 11.937 11.388 STI M 24 × 1.5 Ⅰb 25.948 24.974 24 8 24.324 GH3 38.1 25.4 Ⅰb 30 10 STI 1/2 - 13 UNC 15.238 13.968 13.122 GH3 38.1 25.4 STI 1/2 - 20 UNF Ⅰb 14.350 13.524 18 6 12.976 STI 5/8 - 11 UNC Ⅰb 18.875 17.376 30 10 16.376 STI 5/8 - 18 UNF Ⅰb 17.708 16.791 21 7 16.181 STI 3/4 - 16 UNF Ⅰb 21.112 20.081 21 7 19.392 Technical-33