Parker Hannifin 62NBH-4 Brass Air Brake-NTA Bulkhead Union Fitting, 1/4" Compression Tube x 1/4" Compression Tube D.O.T. Compression style fittings for repairing truck and trailer air brake lines For Use in air brake Systems on semi-trucks, trailers, buses, mobile equipment and farm implements Ribbed sleeve for compression and positive grip Stainless steel tube support Meets D.O.T. FM's 571.106, SAE J246 and SAE J1131