Darson Breather hoses are Co-Extruded with a fuel resistant NBR tube and a Ozone resistant CSM cover. They can withstand vacuum collapse and allows an internal combustion engine to vent crank case pressure out of the engine.  By venting pressure out of the crank case, and engine’s piston rings are allow to seal tighter against the cylinder walls, this provide better compression and promotes less oil consumption while making more horse power. 

Automotive hose