Description
Five-piece assortment of composite-body DOT push-in straight unions covering the full range of common nylon air-brake tubing sizes — 5/32″, 1/4″, 3/8″, 1/2″, and 5/8″ tube OD. UV- and vibration-resistant composite body, no-tool quick-connect. Each fitting meets DOT FMVSS 49 CFR 571.106 and SAE J2494-3 air-brake-system requirements.
Specifications
| Manufacturer | Midland Industries |
|---|---|
| Part Type | DOT Push-In Straight Union (Composite) Assortment |
| Pack Size | 5 fittings (1 of each size) |
| Body | Composite (UV / vibration resistant) |
| Tube OD Range | 5/32″, 1/4″, 3/8″, 1/2″, 5/8″ |
| Standards | DOT FMVSS 49 CFR 571.106 / SAE J2494-3 |
Kit Includes
- 1 × 5/32″ tube OD straight union (composite)
- 1 × 1/4″ tube OD straight union (composite)
- 1 × 3/8″ tube OD straight union (composite)
- 1 × 1/2″ tube OD straight union (composite)
- 1 × 5/8″ tube OD straight union (composite)
Applications
Service-truck or shop kit for splicing or repairing DOT-approved nylon air-brake tubing across the common medium- and heavy-duty truck size range. Composite body is acceptable for air-brake service per DOT/SAE; not for use as a structural fitting or with non-air-brake fluids.
Composite-body unions are interchangeable with brass-body equivalents in air-brake service. For higher-temperature engine-bay routing, the brass equivalents (Midland 620xxx series) are preferred.









