How to Identify and Measure Fittings
Pipe size is an industry designation, not the actual size. View information about how to measure threaded and unthreaded pipe and pipe fittings.
More
About Conduit
More
Low-Pressure Aluminum
Threaded Pipe Fittings
In addition to being lightweight, these aluminum fittings offer good corrosion resistance. Use them in low-pressure flow applications. To prevent cracking, do not tighten more than a 1/4-turn past hand tight.
Locknuts thread onto the male end of a fitting to provide extra holding power so the fitting won’t loosen from vibration.
NPTF (Dryseal) threads and NPSL (National Pipe Straight Locknut) threads are compatible with NPT threads.
For technical drawings and 3-D models, click on a part number.

- For Use With: Air, Oil, Water
- Pressure Class: 150
- Pipe Nipples and Pipe: Use Schedule 40 aluminum
- Flanges: Use Class 125 aluminum
Pipe Size | Max. Pressure | Each | |
NPSL Female | |||
---|---|---|---|
1/4 | 150 psi @ 72° F | 000000000 | 00000 |
3/8 | 150 psi @ 72° F | 000000000 | 0000 |
1/2 | 150 psi @ 72° F | 000000000 | 0000 |
3/4 | 150 psi @ 72° F | 000000000 | 00000 |
1 | 150 psi @ 72° F | 000000000 | 00000 |
1 1/4 | 150 psi @ 72° F | 000000000 | 00000 |
1 1/2 | 150 psi @ 72° F | 000000000 | 00000 |
2 | 150 psi @ 72° F | 000000000 | 00000 |
2 1/2 | 150 psi @ 72° F | 000000000 | 00000 |
3 | 150 psi @ 72° F | 000000000 | 00000 |
Locknuts for Metal Conduit Fittings

Steel, 316 Stainless
Steel, and Aluminum
Secure threaded metal conduit fittings to a knockout in an outlet box or enclosure.
Zinc-plated steel, 316 stainless steel, and aluminum locknuts are compatible with NPSL and NPSM threads.
For technical drawings and 3-D models, click on a part number.