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D.O.T. Brass Compression Tube Fittings for Air

- Temperature Range: -40° to 200° F
- Tubing: Use with hard (Durometer 65D) nylon plastic
- Specifications Met: D.O.T. FMVSS 571
Safe for use in your air brake line, these fittings meet Department of Transportation FMVSS 571 standards. They’ve been tested for thermal cycling, vibration, and burst pressure, so put them to work right away. They have a single sleeve (ferrule) that compresses the tubing as you tighten the included nut, creating a strong seal. All components are made of brass and are corrosion resistant. Also known as flareless fittings.
Fittings with male threaded pipe connection have acrylic thread sealant to stop leaks and prevent loosening on the pipe end.
NPTF (Dryseal) threads are compatible with NPT threads.
For technical drawings and 3-D models, click on a part number.

For Tube OD | Pipe Size | Material | Fitting Seal Type | Max. Pressure | Each | |
NPTF Threads | ||||||
---|---|---|---|---|---|---|
3/16" | 1/8 | Brass | Thread Sealant | 150 psi @ 72° F | 000000000 | 000000 |
1/4" | 1/16 | Brass | Thread Sealant | 150 psi @ 72° F | 000000000 | 00000 |
1/4" | 1/8 | Brass | Thread Sealant | 150 psi @ 72° F | 000000000 | 0000 |
1/4" | 1/4 | Brass | Thread Sealant | 150 psi @ 72° F | 000000000 | 0000 |
1/4" | 3/8 | Brass | Thread Sealant | 150 psi @ 72° F | 000000000 | 00000 |
3/8" | 1/8 | Brass | Thread Sealant | 150 psi @ 72° F | 000000000 | 0000 |
3/8" | 1/4 | Brass | Thread Sealant | 150 psi @ 72° F | 000000000 | 0000 |
3/8" | 3/8 | Brass | Thread Sealant | 150 psi @ 72° F | 000000000 | 0000 |
3/8" | 1/2 | Brass | Thread Sealant | 150 psi @ 72° F | 000000000 | 0000 |
1/2" | 1/4 | Brass | Thread Sealant | 150 psi @ 72° F | 000000000 | 0000 |
1/2" | 3/8 | Brass | Thread Sealant | 150 psi @ 72° F | 000000000 | 00000 |
1/2" | 1/2 | Brass | Thread Sealant | 150 psi @ 72° F | 000000000 | 00000 |
1/2" | 3/4 | Brass | Thread Sealant | 150 psi @ 72° F | 000000000 | 0000 |
5/8" | 3/8 | Brass | Thread Sealant | 150 psi @ 72° F | 000000000 | 0000 |
5/8" | 1/2 | Brass | Thread Sealant | 150 psi @ 72° F | 000000000 | 0000 |
5/8" | 3/4 | Brass | Thread Sealant | 150 psi @ 72° F | 000000000 | 0000 |
3/4" | 1/2 | Brass | Thread Sealant | 150 psi @ 72° F | 000000000 | 00000 |
3/4" | 3/4 | Brass | Thread Sealant | 150 psi @ 72° F | 000000000 | 00000 |

For Tube OD | Pipe Size | Material | Max. Pressure | Each | |
NPTF Threads | |||||
---|---|---|---|---|---|
1/4" | 1/8 | Brass | 150 psi @ 72° F | 000000000 | 00000 |
1/4" | 1/4 | Brass | 150 psi @ 72° F | 000000000 | 0000 |
3/8" | 1/8 | Brass | 150 psi @ 72° F | 000000000 | 0000 |
3/8" | 1/4 | Brass | 150 psi @ 72° F | 000000000 | 0000 |
3/8" | 3/8 | Brass | 150 psi @ 72° F | 000000000 | 00000 |
1/2" | 3/8 | Brass | 150 psi @ 72° F | 000000000 | 00000 |
5/8" | 3/8 | Brass | 150 psi @ 72° F | 000000000 | 00000 |
5/8" | 1/2 | Brass | 150 psi @ 72° F | 000000000 | 00000 |
3/4" | 1/2 | Brass | 150 psi @ 72° F | 000000000 | 00000 |

Fittings with intermittent swivel allow movement in your system by rotating 360° before and after installation. They help keep tubes from kinking.

Through-wall fittings are also known as bulkhead couplings and panel-mount couplings; they mount through your wall or panel to create an inlet or outlet.

For Tube OD | Pipe Size | Material | Fitting Seal Type | Max. Pressure | Each | |
NPTF Threads | ||||||
---|---|---|---|---|---|---|
3/16" | 1/8 | Brass | Thread Sealant | 150 psi @ 72° F | 000000000 | 000000 |
3/16" | 1/4 | Brass | Thread Sealant | 150 psi @ 72° F | 000000000 | 00000 |
1/4" | 1/8 | Brass | Thread Sealant | 150 psi @ 72° F | 000000000 | 0000 |
1/4" | 1/4 | Brass | Thread Sealant | 150 psi @ 72° F | 000000000 | 0000 |
1/4" | 3/8 | Brass | Thread Sealant | 150 psi @ 72° F | 000000000 | 00000 |
3/8" | 1/8 | Brass | Thread Sealant | 150 psi @ 72° F | 000000000 | 0000 |
3/8" | 1/4 | Brass | Thread Sealant | 150 psi @ 72° F | 000000000 | 0000 |
3/8" | 3/8 | Brass | Thread Sealant | 150 psi @ 72° F | 000000000 | 0000 |
3/8" | 1/2 | Brass | Thread Sealant | 150 psi @ 72° F | 000000000 | 00000 |
1/2" | 3/8 | Brass | Thread Sealant | 150 psi @ 72° F | 000000000 | 00000 |
1/2" | 1/2 | Brass | Thread Sealant | 150 psi @ 72° F | 000000000 | 00000 |
5/8" | 1/2 | Brass | Thread Sealant | 150 psi @ 72° F | 000000000 | 00000 |
5/8" | 3/4 | Brass | Thread Sealant | 150 psi @ 72° F | 000000000 | 00000 |
3/4" | 1/2 | Brass | Thread Sealant | 150 psi @ 72° F | 000000000 | 00000 |
3/4" | 3/4 | Brass | Thread Sealant | 150 psi @ 72° F | 000000000 | 00000 |

Fittings with intermittent swivel allow movement in your system by rotating 360° before and after installation. They help keep tubes from kinking.
For Tube OD | Pipe Size | Material | Fitting Seal Type | Max. Pressure | Each | |
NPTF Threads | ||||||
---|---|---|---|---|---|---|
3/8" | 3/8 | Brass | Thread Sealant | 150 psi @ 72° F | 000000000 | 000000 |

For Tube OD | Pipe Size | Material | Fitting Seal Type | Max. Pressure | Each | |
NPTF Threads | ||||||
---|---|---|---|---|---|---|
3/8" | 1/4 | Brass | Thread Sealant | 150 psi @ 72° F | 000000000 | 000000 |

For Tube OD | Pipe Size | Material | Fitting Seal Type | Max. Pressure | Each | |
NPTF Threads | ||||||
---|---|---|---|---|---|---|
1/4" | 1/8 | Brass | Thread Sealant | 150 psi @ 72° F | 000000000 | 00000 |
1/4" | 1/4 | Brass | Thread Sealant | 150 psi @ 72° F | 000000000 | 0000 |
3/8" | 1/4 | Brass | Thread Sealant | 150 psi @ 72° F | 000000000 | 0000 |
3/8" | 3/8 | Brass | Thread Sealant | 150 psi @ 72° F | 000000000 | 0000 |
1/2" | 3/8 | Brass | Thread Sealant | 150 psi @ 72° F | 000000000 | 0000 |
Sleeves for D.O.T. Brass Compression Tube Fittings for Air

- Tubing: Use with hard (Durometer 65D) nylon plastic
- Specifications Met: D.O.T. FMVSS 571
- Temperature Range: -40° to 200° F
Use these sleeves with D.O.T. brass compression nuts and fittings to create a seal on nylon tubing. They are brass for good corrosion resistance.
For technical drawings and 3-D models, click on a part number.
Nuts for D.O.T. Brass Compression Tube Fittings for Air

- Tubing: Use with hard (Durometer 65D) nylon plastic
- Specifications Met: D.O.T. FMVSS 571
- Temperature Range: -40° to 200° F
Use these nuts with D.O.T. brass compression sleeves and fittings to create a seal on nylon tubing. They are brass for good corrosion resistance.
For technical drawings and 3-D models, click on a part number.
Tight-Seal Brass Compression Tube Fittings for Air and Water

- Temperature Range: -65° to 250° F
- Tubing: Use with firm (Durometer 95A) EVA plastic or polyurethane rubber
- Specifications Met: SAE J512
A built-in tube support slips inside the tubing to prevent collapsing and provides a sturdy connection for an extra-tight seal. Fittings have a single sleeve (ferrule) that compresses the tubing as you tighten the nut. The nut and sleeve are included. Fittings are also known as flareless fittings. They are brass for good corrosion resistance.
For technical drawings and 3-D models, click on a part number.

For Tube OD | Pipe Size | Material | Max. Pressure | Each | |
NPT Threads | |||||
---|---|---|---|---|---|
1/4" | 1/8 | Brass | 90 psi @ 72° F | 00000000 | 00000 |
1/4" | 1/4 | Brass | 90 psi @ 72° F | 00000000 | 0000 |
1/4" | 3/8 | Brass | 90 psi @ 72° F | 00000000 | 0000 |
1/4" | 1/2 | Brass | 90 psi @ 72° F | 00000000 | 0000 |
1/4" | 3/4 | Brass | 90 psi @ 72° F | 000000000 | 00000 |
3/8" | 1/8 | Brass | 90 psi @ 72° F | 00000000 | 0000 |
3/8" | 1/4 | Brass | 90 psi @ 72° F | 00000000 | 0000 |
3/8" | 3/8 | Brass | 90 psi @ 72° F | 00000000 | 0000 |
3/8" | 1/2 | Brass | 90 psi @ 72° F | 00000000 | 0000 |
3/8" | 3/4 | Brass | 90 psi @ 72° F | 000000000 | 00000 |
1/2" | 1/4 | Brass | 90 psi @ 72° F | 000000000 | 0000 |
1/2" | 3/8 | Brass | 90 psi @ 72° F | 00000000 | 0000 |
1/2" | 1/2 | Brass | 90 psi @ 72° F | 00000000 | 0000 |
5/8" | 1/2 | Brass | 90 psi @ 72° F | 000000000 | 00000 |

For Tube OD | Pipe Size | Material | Max. Pressure | Each | |
NPT Threads | |||||
---|---|---|---|---|---|
1/4" | 1/8 | Brass | 90 psi @ 72° F | 00000000 | 00000 |
1/4" | 1/4 | Brass | 90 psi @ 72° F | 00000000 | 0000 |
1/4" | 3/8 | Brass | 90 psi @ 72° F | 00000000 | 0000 |
1/4" | 1/2 | Brass | 90 psi @ 72° F | 00000000 | 00000 |
3/8" | 1/8 | Brass | 90 psi @ 72° F | 00000000 | 0000 |
3/8" | 1/4 | Brass | 90 psi @ 72° F | 00000000 | 0000 |
3/8" | 3/8 | Brass | 90 psi @ 72° F | 00000000 | 0000 |
3/8" | 1/2 | Brass | 90 psi @ 72° F | 00000000 | 0000 |
1/2" | 3/8 | Brass | 90 psi @ 72° F | 00000000 | 0000 |
1/2" | 1/2 | Brass | 90 psi @ 72° F | 00000000 | 00000 |

Fittings with 45° female flared tube end have an internal flare that mates with a male 45° flared fitting.
For Tube OD (A) | For Tube OD (B) | Material | Max. Pressure | Each | |
UN/UNF (SAE 45°) Threads | |||||
---|---|---|---|---|---|
3/8" | 1/4" | Brass | 90 psi @ 72° F | 00000000 | 00000 |

For Tube OD | Pipe Size | Material | Max. Pressure | Each | |
NPT Threads | |||||
---|---|---|---|---|---|
1/4" | 1/8 | Brass | 90 psi @ 72° F | 00000000 | 00000 |
1/4" | 1/4 | Brass | 90 psi @ 72° F | 00000000 | 0000 |
1/4" | 3/8 | Brass | 90 psi @ 72° F | 00000000 | 0000 |
1/4" | 1/2 | Brass | 90 psi @ 72° F | 00000000 | 00000 |
3/8" | 1/8 | Brass | 90 psi @ 72° F | 00000000 | 0000 |
3/8" | 1/4 | Brass | 90 psi @ 72° F | 00000000 | 0000 |
3/8" | 3/8 | Brass | 90 psi @ 72° F | 00000000 | 0000 |
3/8" | 1/2 | Brass | 90 psi @ 72° F | 00000000 | 0000 |
1/2" | 1/4 | Brass | 90 psi @ 72° F | 000000000 | 00000 |
1/2" | 3/8 | Brass | 90 psi @ 72° F | 00000000 | 0000 |
1/2" | 1/2 | Brass | 90 psi @ 72° F | 00000000 | 00000 |

For Tube OD | Pipe Size | Material | Max. Pressure | Each | |
NPT Threads | |||||
---|---|---|---|---|---|
1/4" | 1/8 | Brass | 90 psi @ 72° F | 00000000 | 00000 |
1/4" | 1/4 | Brass | 90 psi @ 72° F | 00000000 | 0000 |
1/4" | 3/8 | Brass | 90 psi @ 72° F | 00000000 | 00000 |
1/4" | 1/2 | Brass | 90 psi @ 72° F | 00000000 | 00000 |
3/8" | 1/8 | Brass | 90 psi @ 72° F | 00000000 | 00000 |
3/8" | 1/4 | Brass | 90 psi @ 72° F | 00000000 | 0000 |
3/8" | 3/8 | Brass | 90 psi @ 72° F | 00000000 | 0000 |
1/2" | 3/8 | Brass | 90 psi @ 72° F | 00000000 | 00000 |
1/2" | 1/2 | Brass | 90 psi @ 72° F | 00000000 | 00000 |

Inline tees are also known as branch tees.
For Tube OD | Pipe Size | Material | Max. Pressure | Each | |
NPT Threads | |||||
---|---|---|---|---|---|
1/4" | 1/8 | Brass | 90 psi @ 72° F | 00000000 | 00000 |
1/4" | 1/4 | Brass | 90 psi @ 72° F | 00000000 | 00000 |
3/8" | 1/8 | Brass | 90 psi @ 72° F | 00000000 | 00000 |
3/8" | 1/4 | Brass | 90 psi @ 72° F | 00000000 | 00000 |
3/8" | 3/8 | Brass | 90 psi @ 72° F | 00000000 | 00000 |
1/2" | 3/8 | Brass | 90 psi @ 72° F | 00000000 | 00000 |
1/2" | 1/2 | Brass | 90 psi @ 72° F | 00000000 | 00000 |

Inline tees are also known as branch tees.
For Tube OD (A) | For Tube OD (B) | Material | Max. Pressure | Each | |
3/8" | 1/4" | Brass | 90 psi @ 72° F | 00000000 | 000000 |
Sleeves for Tight-Seal Brass Compression Tube Fittings for Air and Water

- Tubing: Use with firm (Durometer 95A) EVA plastic or polyurethane rubber
- Specifications Met: SAE J512
- Temperature Range: -65° to 250° F
Use these sleeves with tight-seal brass compression nuts and fittings to create a seal on plastic and rubber tubing. They are acetal, so they won’t damage tubing.
For technical drawings and 3-D models, click on a part number.
Nuts for Tight-Seal Brass Compression Tube Fittings for Air and Water

- Tubing: Use with firm (Durometer 95A) EVA plastic or polyurethane rubber
- Specifications Met: SAE J512
- Temperature Range: -65° to 250° F
Use these nuts with tight-seal brass compression sleeves and fittings to create a seal on plastic and rubber tubing. They are brass for good corrosion resistance.
For technical drawings and 3-D models, click on a part number.
Plastic Compression Tube Fittings for Water

- Temperature Range: -40° to 200° F
- Tubing: Use with firm or hard (Durometer 1A-90A or Durometer OD-75D) nylon plastic or polypropylene plastic
Made of acetal, these compression fittings are lighter in weight than metal compression fittings and won’t absorb moisture when used in wet environments. Fittings include a nut with a built-in sleeve (ferrule), so there’s no need to remove the nut for assembly. The sleeve compresses the tubing as you tighten the nut, creating a strong seal. Fittings are also known as flareless fittings.
Tube supports (sold separately) are recommended if you want to use the fittings with soft nylon and polypropylene tubing to prevent the tube from collapsing.
For technical drawings and 3-D models, click on a part number.