... :2000, DOT certificate Trailer air brake reinforced hose :• Material:PA,PU,double nylon tube• Hose size(OD*ID):12×9,12×8 ... /coil:12,16,18,20,22,24,26,28,30 coils.etc.• Stretched length:5m,5.5m,6.5m,7.5m ... (Polyurethane) TubeTubing -- PU (Polyurethane) air brake coils, spiral hoseDouble tube--Trailer air brake reinforced hose, air brake coil with double layerDouble tubing ...