SAE O-Ring Boss

SAE Straight Thread O-ring or O-Ring Boss (ORB) is a multipurpose thread ideal for medium and high-pressure hydraulic applications. The male thread contains an o-ring at the base which mates with a chamfer machined into the female counterpoint, which makes this thread type ideal for non-leak applications.

In order to properly identify ORB threads, please consult the outside and inside diameters of male and female threads respectively. Each of our ORB fittings contain a thread chart in the description for your convenience. Torque specifications and pressure ratings can be found within our resources as well.

SAE O-Ring Boss
Inch Size
Dash Size
Nominal Size
Male OD
Female ID
1/8
02
5/16-24
.31
.27
3/16
03
3/8-24
.38
.34
1/4
04
7/16-20
.44
.39
5/16
05
1/2-20
.50
.45
3/8
06
9/16-18
.56
.51
1/2
08
3/4-16
.75
.69
5/8
10
7/8-14
.88
.81
3/4
12
1-1/16 -12
1.06
.98
7/8
14
1-13/16 -12
1.19
1.10
1
16
1-5/16 - 12
1.31
1.23
1-1/4
20
1-5/8 - 12
1.63
1.54
1-1/2
24
1-7/8 -12
1.88
1.79
2
32
2-1/2 - 12
2.50
2.42
Inch Size
Dash Size
Nominal Size
Male OD
Female ID
1/8
02
5/16-24
.31
.27
3/16
03
3/8-24
.38
.34
1/4
04
7/16-20
.44
.39
5/16
05
1/2-20
.50
.45
3/8
06
9/16-18
.56
.51
1/2
08
3/4-16
.75
.69
5/8
10
7/8-14
.88
.81
3/4
12
1-1/16 -12
1.06
.98
7/8
14
1-13/16 -12
1.19
1.10
1
16
1-5/16 - 12
1.31
1.23
1-1/4
20
1-5/8 - 12
1.63
1.54
1-1/2
24
1-7/8 -12
1.88
1.79
2
32
2-1/2 - 12
2.50
2.42
Inch Size
Dash Size
Nominal Size
Male OD
Female ID
1/8
1/4
3/8
1/2
3/4
1
1-1/4
1-1/2
2
02
04
06
08
12
16
20
24
32
5/16-24
1/4-18
3/8-18
1/2-14
3/4-14
1-11.5
1-1/4 - 11.5
1-1/2 -11.5
2-11.5
.31
.54
.68
.84
1.05
1.32
1.66
1.90
2.38
.27
.49
.63
.77
.98
1.24
1.58
1.82
2.30
Inch Size
Dash Size
Nominal Size
Male OD
Female ID
1/4
04
9/16-18
.56
.51
3/8
06
11/16-16
.69
.63
1/2
08
3/16-16
.82
.75
5/8
10
1-14
1.00
.93
3/4
12
1-3/16 - 12
1.19
1.11
1
16
1-7/16 - 12
1.44
1.36
1-1/4
20
1-11/16 -12
1.69
1.61
1-1/2
24
2-12
2.00
1.92