This hose meets the standards for DOT FMVSS 106 AIR BRAKE - AI, SAE J1402 AI, has a maximum operating pressure of 450 psi @ 70 Degrees F, has an operating temperature of -58 Degrees to 302 Degrees F and is made of Nylon. In addition, it has 3¼ inch outside diameter, 3¼ inch inside diameter. This hose is for use on hydraulic fluid.