American Dryseal Pipe Threads (NPTF & NPSM)
DASH SIZE
INCH SIZE
THREAD
MALE
THREAD

O.D.
(mm)
MALE
THREAD

O.D.
(inches)
FEMALE
THREAD

I.D.
(mm)
FEMALE
THREAD

I.D.
(inches)
2
1/8
1/8-27
10.3
.41
9.4
.37
4
1/4
1/4-18
13.7
.54
12.4
.49
6
3/8
3/8-18
17.3
.68
15.7
.62
8
1/2
1/2-14
21.3
.84
19.3
.76
12
3/4
3/4-14
26.9
1.06
24.9
.98
16
1
1-11 1/2
33.3
1.31
31.5
1.24
20
1 1/4
1 1/4-11 1/2
42.2
1.66
40.1
1.58
24
1 1/2
1 1/2-11 1/2
48.3
1.90
46.2
1.82
32
2
2-11 1/2
60.4
2.38
57.9
2.29

*Conforms to ASME/ANSI B1.20.1 industry standards*