Superior Air Line: Our air brake hose is made of High-quality PA12 Nylon material, thicker and better quality than others. 3-layer integrated molding with uniform thickness, featured excellent flexibility, good wear resistant and not harden under cold weather Safer Anti-Kinking Design: Red blue air lines are equipped with spring protection sleeve, can prevent air hose from kinking, ensure easy isntallation in tight spaces, good adaptation to semi truck in the turn of the telescopic Replacement: For ectran 17215-040, Tremec Sloan️ 451039N, Philips️ 11-340, etc., this air brake coiled/hoses assembly reach OEM standard, meet SAE J844 and DOT FMVSS 106, a perfect replacement for damaged hoses Dimension: Air Brake Coiled Hoses Length: 15 Feet, Tractor Lead Length: 40'', Trailer Lead Length: 12'', DOT Brass Fitting: 1/2'' NPT thread. Non-fading & Non-leakage: The color of hose is mixed in the raw material, not by spray paint, thus not fade.Dual ends are solid brass fittings with sealant, difficult to fall off, ensure steady and long-term connection, no air leakage. 1