USA-made CNC-machined NPT full couplings from 6061-T6 aluminum bar. Meet or exceed SCH 40 wall for 150# rating. Threadable from both ends. Sizes 1/8"–4" NPT.
Made in USA (in-house)
Thread profile per ASME B1.20.1
Quality-checked with L1 thread gauge
Not replaced after welding
NPT sizes refer to the pipe that threads into the fitting. Threads have a 1.8° taper — male fittings typically tighten 1 turn or less past hand-tight. Use appropriate thread sealant.
SKU
NPT
ID
OD
Height
TPI
21031
1/8"
0.330"
0.600"
0.870"
27
21016
1/4"
0.450"
0.750"
1.000"
18
21017
3/8"
0.580"
0.910"
1.140"
18
21018
1/2"
0.750"
1.060"
1.300"
14
21019
3/4"
0.950"
1.292"
1.520"
14
21020
1"
1.170"
1.625"
1.760"
11.5
21064
1.5"
1.750"
2.235"
2.240"
11.5
21055
2"
2.250"
2.750"
2.500"
11.5
21071
3"
3.280"
3.930"
3.060"
8
4" NPT (#21073) is also available in the drop-down. Chart dims above cover through 3".
