... DOT certificate Trailer air brake reinforced hose :• Material:PA,PU,double nylon tube• Hose size(OD*ID):12×9,12× ... M16,M18 ,M22 ,1/2"fittings etc. or no fitting• Type:European style, American style, ordinary type-----------------------------------------NicholeMob.: +86 ... brake coils, spiral hoseDouble tube--Trailer air brake reinforced hose, air brake coil with double layerDouble tubing--Double layer ...