Metric
Insert Size Drill Size Wire Thread Insert Length
1D 1.5D 2D 2.5D 3D

M2 x 0.4

2.10 2.00 3.00 4.00 5.00 6.00

M2.2 x 0.45

2.30 2.20 3.30 4.40 5.50 6.60

M2.5 x 0.45

2.60 2.50 3.75 5.00 6.25 7.50

M3 x 0.5

3.10 3.00 4.50 6.00 7.50 9.00

M3.5 x 0.6

3.60 3.50 5.25 7.00 8.75 10.50

M4 x 0.7

4.10 4.00 6.00 8.00 10.00 12.00

M4.5 x 0.75

4.70 4.50 6.75 9.00 11.25 13.50

M5 x 0.8

5.20 5.00 7.50 10.00 12.50 15.00

M6 x 1.0

6.20 6.00 9.00 12.00 15.00 18.00

M7 x 1.0

7.20 7.00 10.50 14.00 17.50 21.00

M8 x 1.0

8.20 8.00 12.00 16.00 20.00 24.00

M8 x 1.25

8.30 8.00 12.00 16.00 20.00 24.00

M9 x 1.25

9.30 9.00 13.50 18.00 22.50 27.00

M10 x 1.0

10.30 10.00 15.00 20.00 25.00 30.00

M10 x 1.25

10.30 10.00 15.00 20.00 25.00 30.00

M10 x 1.5

10.30 10.00 15.00 20.00 25.00 30.00

M11 x 1.5

11.30 11.00 16.50 22.00 27.50 33.00

M12 x 1.25

12.30 12.00 18.00 24.00 30.00 36.00

M12 x 1.5

12.40 12.00 18.00 24.00 30.00 36.00

M12 x 1.75

12.40 12.00 18.00 24.00 30.00 36.00

M14 x 1.25

14.30 14.00 21.00 28.00 35.00 42.00

M14 x 1.5

14.30 14.00 21.00 28.00 35.00 42.00

M14 x 2.0

14.30 14.00 21.00 28.00 35.00 42.00

M16 x 1.5

16.25 16.00 24.00 32.00 40.00 48.00

M16 x 2.0

16.50 16.00 24.00 32.00 40.00 48.00

M18 x 1.5

18.25 18.00 27.00 36.00 45.00 54.00

M18 x 2.0

18.50 18.00 27.00 36.00 45.00 54.00

M18 x 2.5

18.50 18.00 27.00 36.00 45.00 54.00

M20 x 1.5

20.25 20.00 30.00 40.00 50.00 60.00

M20 x 2.0

20.50 20.00 30.00 40.00 50.00 60.00

M20 x 2.5

20.50 20.00 30.00 40.00 50.00 60.00

M22 x 1.5

22.50 22.00 33.00 44.00 55.00 66.00

M22 x 2.0

22.50 22.00 33.00 44.00 55.00 66.00

M22 x 2.5

22.50 22.00 33.00 44.00 55.00 66.00

M24 x 1.5

24.25 24.00 36.00 48.00 60.00 72.00

M24 x 2.0

24.25 24.00 36.00 48.00 60.00 72.00

M24 x 3.0

24.75 24.00 36.00 48.00 60.00 72.00

M27 x 2

27.50 27.00 40.50 54.00 67.50 81.00

M27 x 3.0

27.50 27.00 40.50 54.00 67.50 81.00

M30 x 1.5

30.50 30.00 45.00 60.00 75.00 90.00

M30 x 2.0

30.50 30.00 45.00 60.00 75.00 90.00

M30 x 3.5

30.50 30.00 45.00 60.00 75.00 90.00

M33 x 2.0

33.50 33.00 49.50 66.00 82.50 99.00

M36 x 2.0

36.50 36.00 54.00 72.00 90.00 108.00

M36 x 4.0

36.50 36.00 54.00 72.00 90.00 108.00

M39 x 2.0

39.50 39.00 58.50 78.00 97.50 117.00

M39 x 4.0

39.50 39.00 58.50 78.00 97.50 117.00
UNC
Insert Size Drill Size Wire Thread Insert Length
1D 1.5D 2D 2.5D 3D

2-56

2.3 mm 0.086 0.129 0.172 0.215 0.258

3-48

2.7 mm 0.099 0.148 0.198 0.248 0.297

4-40

3.0 mm 0.112 0.168 0.224 0.280 0.336

5-40

3.4 mm 0.125 0.188 0.250 0.312 0.375

6-32

3.7 mm 0.138 0.207 0.276 0.345 0.414

8-32

11/64 0.164 0.246 0.328 0.410 0.492

10-24

5.1 mm 0.190 0.285 0.380 0.475 0.570

12-24

5.8 mm 0.216 0.324 0.432 0.540 0.648

1/4-20

6.7 mm 0.250 0.375 0.500 0.625 0.750

5/16-18

8.3 mm 0.312 0.469 0.625 0.781 0.938

3/8-16

9.9 mm 0.375 0.562 0.750 0.938 1.125

7/16-14

29/64 0.438 0.656 0.875 1.094 1.313

1/2-13

33/64 0.500 0.750 1.000 1.250 1.500

9/16-12

14.75 mm 0.562 0.844 1.125 1.406 1.688

5/8-11

16.5 mm 0.625 0.938 1.250 1.563 1.875

3/4-10

19.75 mm 0.750 1.125 1.500 1.875 2.250

7/8-9

23.0 mm 0.875 1.313 1.750 2.188 2.625

1-8

1-1/32 1.000 1.500 2.000 2.500 3.000

1.1/8-7

1-5/32 1.125 1.688 2.250 2.813 3.375

1.1/4-7

1-9/32 1.250 1.875 2.500 3.125 3.750

1.3/8-6

36.0 1.375 2.063 2.750 3.438 4.125

1.1/2-6

1-35/64 1.500 2.250 3.000 3.750 4.500
UNF
Insert Size Drill Size Wire Thread Insert Length
1D 1.5D 2D 2.5D 3D

2-64

2.3 mm 0.086 0.129 0.172 0.215 0.258

3-56

2.65 mm 0.099 0.148 0.198 0.248 0.297

4-48

3.0 mm 0.112 0.168 0.224 0.280 0.336

5-44

3.3 mm 0.125 0.188 0.250 0.312 0.375

6-40

3.7 mm 0.138 0.207 0.276 0.345 0.414

8-36

11/64 0.164 0.246 0.328 0.410 0.492

10-32

5.1 mm 0.190 0.285 0.380 0.475 0.570

1/4-28

6.6 mm 0.250 0.375 0.500 0.625 0.750

5/16-24

8.2 mm 0.312 0.469 0.625 0.781 0.938

3/8-24

9.8 mm 0.375 0.562 0.750 0.938 1.125

7/16-20

29/64 0.438 0.656 0.875 1.094 1.313

1/2-20

33/64 0.500 0.750 1.000 1.250 1.500

9/16-18

37/64 0.562 0.844 1.125 1.406 1.688

5/8-18

41/64 0.625 0.938 1.250 1.563 1.875

3/4-16

49/64 0.750 1.125 1.500 1.875 2.250

7/8-14

22.75 mm 0.875 1.313 1.750 2.188 2.625

1-12

26.0 mm 1.000 1.500 2.000 2.500 3.000

1.1/8-12

29.25 mm 1.125 1.688 2.250 2.813 3.375

1.1/4-12

1-17/64 1.250 1.875 2.500 3.125 3.750

1.3/8-12

35.5 mm 1.375 2.063 2.750 3.438 4.125

1.1/2-12

38.5 mm 1.500 2.250 3.000 3.750 4.500
BSW
Insert Size Drill Size Wire Thread Insert Length
1D 1.5D 2D 2.5D 3D

1/8-40

3.3 mm 0.125 0.188 0.250 0.313 0.375

3/16-24

5.0 mm 0.188 0.281 0.375 0.469 0.563

1/4-20

6.7 mm 0.250 0.375 0.500 0.625 0.750

5/16-18

21/64 0.313 0.469 0.625 0.781 0.938

3/8-16

25/64 0.375 0.563 0.750 0.938 1.125

7/16-14

29/64 0.438 0.656 0.875 1.094 1.313

1/2-12

33/64 0.500 0.750 1.000 1.250 1.500

9/16-12

37/64 0.562 0.844 1.125 1.406 1.688

5/8-11

21/32 0.625 0.938 1.250 1.563 1.875

11/16-11

23/32 0.688 1.031 1.375 1.719 2.063

3/4-10

25/32 0.750 1.125 1.500 1.875 2.250

7/8-9

29/32 0.875 1.313 1.750 2.188 2.625

1-8

1-1/32 1.000 1.500 2.000 2.500 3.000

1.1/8-7

1-11/64 1.125 1.688 2.250 2.813 3.375

1.1/4-7

1-19/64 1.250 1.875 2.500 3.125 3.750

1.1/2-6

1-35/64 1.500 2.250 3.000 3.750 4.500
BSF
Insert Size Drill Size Wire Thread Insert Length
1D 1.5D 2D 2.5D 3D

3/16-32

4.9 mm 0.188 0.281 0.375 0.469 0.563

7/32-28

5.8 mm 0.219 0.328 0.438 0.547 0.656

1/4-26

6.6 mm 0.250 0.375 0.500 0.625 0.750

9/32-26

7.4 mm 0.281 0.422 0.563 0.703 0.844

5/16-22

8.3 mm 0.313 0.469 0.625 0.781 0.938

3/8-20

9.8 mm 0.375 0.563 0.750 0.938 1.125

7/16-18

29/64 0.438 0.656 0.875 1.094 1.313

1/2-16

33/64 0.500 0.750 1.000 1.250 1.500

9/16-16

37/64 0.563 0.844 1.125 1.406 1.688

5/8-14

41/64 0.625 0.938 1.250 1.563 1.875

11/16-14

45/64 0.688 1.031 1.375 1.719 2.063

3/4-12

49/64 0.750 1.125 1.500 1.875 2.250

13/16-12

53/64 0.813 1.219 1.625 2.031 2.438

7/8-11

57/64 0.875 1.313 1.750 2.188 2.625

1-10

1-1/32 1.000 1.500 2.000 2.500

1.1/8-9

1-5/32 1.125 1.688 2.250 2.813

1.1/4-9

1-9/32 1.250 1.875 2.500 3.125

1.3/8-8

1-13/32 1.375 2.063 2.750

1.1/2-8

1-17/32 1.500 2.250 3.000
G (BSPF)
Insert Size Drill Size Screw Thread Insert Length
1D 1.5D 2D 2.5D 3D

1/8-28

25/64 0.125 0.188 0.250 0.313 0.375

1/4-19

17/32 0.250 0.375 0.500 0.625 0.750

3/8-19

43/64 0.375 0.563 0.750 0.938 1.125

1/2-14

27/32 0.500 0.750 1.000 1.250 1.500

5/8-14

59/64 0.625 0.938 1.250 1.563 1.875

3/4-14

1-1/6 0.750 1.125 1.500 1.875

7/8-14

1-13/64 0.875 1.313 1.750
2.625

1-11

1-21/64 1.000 1.500 2.000

1.1/4-11

1-43/64 1.250 1.875 2.500
3.750

1.1/2-11

1-29/32 1.500 2.250 3.000
4.500
BA
Insert Size Drill Size Screw Thread Insert Length
1D 1.5D 2D 2.5D 3D

0BA

6.2 mm 0.236 0.354 0.472 0.590 0.708

1BA

5.5 mm 0.209 0.313 0.418 0.522 0.627

2BA

4.9 mm 0.185 0.277 0.370 0.462 0.555

3BA

4.3 mm 0.161 0.241 0.322 0.402 0.483

4BA

3.8 mm 0.142 0.213 0.284 0.355 0.426

5BA

3.3 mm 0.126 0.189 0.252 0.315 0.378

6BA

2.9 mm 0.110 0.165 0.220 0.275 0.330