Northway Power Products 3/8" Air Brake DOT Push-In Straight Union allowing you to skip the use of installation tools with a simple Push To Connect (PTC) fitting. Serving as a connector for the air brake tubing, this brass union is perfect to use for tight fit applications under the dash. This union is approved for most air brake applications, except for frame to axle installation, and between towed and towing vehicles. Engineered as a full flow design, gain 60% improved flow than standard compression fittings with inserts. FleetPride is your First Click in Heavy Duty®.