Description
Composite DOT push-to-connect male connector that joins 5/32″ nylon air-brake tubing to a 1/16″ male NPT pipe boss with an instant collet release. The Midland Industries 685301C is rated for SAE J2494-3 push-to-connect service and DOT FMVSS 571.106 air-brake circuits — typical use is small instrumentation, gauge, and pilot-air lines on tractors, trailers, and vocational trucks.
Signs You Need a New Push-to-Connect Fitting
- Audible air leak at the collet or thread interface
- Tubing slips out under pressure or won’t fully seat
- Cracked or chalky composite body from UV / road salt exposure
- Slow brake-circuit pressure build or ABS DTCs tied to a leaking line
Specifications
| Manufacturer | Midland Industries |
|---|---|
| Part Number | 685301C |
| Part Type | DOT Push-to-Connect Male Connector |
| Tube OD | 5/32″ |
| Pipe Thread | 1/16″ Male NPT |
| Body Material | Composite (glass-reinforced thermoplastic) |
| Standards | SAE J2494-3, DOT FMVSS 49 CFR 571.106, SAE J1131 tubing |
Applications
Used in DOT-approved air-brake and pneumatic circuits on:
- Tractor and trailer service / supply lines (small-bore branches)
- Vocational truck pilot-air and gauge lines
- Bus and motorcoach pneumatic accessory circuits
Use only with SAE J1131 nylon air-brake tubing. Inspect collet retention after each tubing reinstallation.









