Made in Japan
Manufacturer: Eisen Co., Ltd.
Model: SPU Series
Unified thread plug gauge (steel thread gauge)
About the Series
Shape
UNC (Unified Coarse) = represents the type of thread
3/8 (inch) = outer diameter of the screw
16 (16 threads per inch) = Pitch expressed as number of threads per inch
Series Details
Example of notation
List of Unified Thread Nominal and Number of Threads
| Call |
Outside diameter |
Number of threads (threads/inch) |
Number of threads (threads/inch) Thread series |
| inch |
Milli |
UNC |
UNF |
UNEF |
4. UN |
6 UN |
8 UN |
12. UN |
16 UN |
20 UN |
28 UN |
32 UN |
| No. 0
No. 2 |
No. 1 |
0.0600
0.0730
0.0860 |
1.524
1.854
2.184 |
64
56 |
80
72
64 |
|
|
|
|
|
|
|
|
|
No. 4
No. 5 |
No. 3 |
0.0990
0.1120
0.1250 |
2.515
2.845
3.175 |
48
40
40 |
56
48
44 |
|
|
|
|
|
|
|
|
|
No. 6
No. 8
No. 10 |
|
0.1380
0.1640
0.1900 |
3.505
4.166
4.826 |
32
32
24 |
40
36
32 |
|
|
|
|
|
|
|
|
|
|
1/4 |
No.12 |
0.2160
0.2500 |
5.486
6.350 |
24
20 |
28
28 |
32
32 |
|
|
|
|
|
|
|
|
5/16
3/8
7/16 |
|
0.3125
0.3750
0.4375 |
7.938
9.525
11.113 |
18
16
14 |
24
24
20 |
32
32
28 |
|
|
|
|
16 |
20
20 |
28
28 |
32 |
1/2
9/16
5/8 |
|
0.5000
0.5625
0.6250 |
12.700
14.288
15.875 |
13
12
11 |
20
18
18 |
28
24
24 |
|
|
|
12 |
16
16
16 |
20
20 |
28
28 |
32
32
32 |
|
3/4 |
11/16
13/16 |
0.6875
0.7500
0.8125 |
17.463
19.050
20.638 |
Ten |
16 |
24
20
20 |
|
|
|
12
12
12 |
16
16 |
20 |
28
28
28 |
32
32
32 |
| 7/8
1 |
15/16 |
0.8750
0.9375
1.0000 |
22.225
23.813
25.400 |
9
8 |
14
12 |
20
20
20 |
|
|
|
12
12 |
16
16
16 |
|
28
28
28 |
32
32
32 |
|
1 1/8 |
1 1/16
1 3/16 |
1.0625
1.1250
1.1875 |
26.988
28.575
30.163 |
7 |
12 |
18
18
18 |
|
|
8
8
8 |
12
12 |
16
16
16 |
20
20
20 |
28
28
28 |
|
| 1 1/4
1 3/8 |
1 5/16 |
1.2500
1.3125
1.3750 |
31.750
33.338
34.925 |
7
6 |
12
12 |
18
18
18 |
|
|
8
8
8 |
12 |
16
16
16 |
20
20
20 |
28
28
28 |
|
|
1 1/2 |
1 7/16
1 9/16 |
1.4375
1.5000
1.5625 |
36.513
38.100
39.688 |
6 |
12 |
18
18
18 |
|
6
6 |
8
8
8 |
12
12 |
16
16
16 |
20
20
20 |
28
28 |
|
| 1 5/8
1 3/4 |
1 11/16 |
1.6250
1.6875
1.7500 |
41.275
42.863
44.450 |
Five |
|
18
18 |
|
6
6
6 |
8
8
8 |
12
12
12 |
16
16
16 |
20
20
20 |
|
|
|
1 7/8 |
1 13/16
1 15/16 |
1.8125
1.8750
1.9375 |
46.038
47.625
49.213 |
|
|
|
|
6
6
6 |
8
8
8 |
12
12
12 |
16
16
16 |
20
20
20 |
|
|
| 2 |
|
2.0000 |
50.800 |
4 1/2 |
|
|
|
6 |
8 |
12 |
16 |
20 |
|
|
- Note: Unified threads that do not fall into any of the above categories are UNS (special threads).
