Description
Brass straight female-NPTF connector with DOT push-in tube end (Midland 660-series), used to terminate nylon air-brake tubing into a female pipe-thread port — typically a tee, manifold, valve, or bulkhead fitting. All-brass body with captive eyelet for full flow; meets DOT FMVSS 571.106 and SAE J1131 air-brake-system requirements.
Specifications
| Manufacturer | Midland Industries |
|---|---|
| Part Numbers | 660402 (1/4″ x 1/8″), 660602 (3/8″ x 1/8″), 660404 (1/4″ x 1/4″), 660604 (3/8″ x 1/4″), 660804 (1/2″ x 1/4″) |
| Part Type | DOT Push-In Female-NPTF Connector |
| Material | Brass |
| Tube OD | 1/4″, 3/8″, 1/2″ (varies by SKU) |
| Thread | 1/8″ or 1/4″ Female NPTF (varies by SKU) |
| Standards | DOT FMVSS 571.106 / SAE J1131 |
Applications
Connecting DOT-approved nylon air-brake tubing to a female-threaded port on tractors, trailers, and vocational trucks. Common service points: brake-valve inlet/outlet ports, air-tank fittings, pressure-protection valves, dryer outlets, and bulkhead manifolds.
Select the variant matching both your tubing OD and the female NPTF thread size of the port you are connecting to.
