With steel breather valve spacer set for correct end play. High quality steel breather valve for use as stock or high performance replacement. Note: S&S breather valves come with elongated breather holes to increase the duration of the vacuum; allowing more oil to be drawn from the cylinder heads. This has no disadvantage in any model year; either stock or Big Inch motor. Note: A .030″ oversize breather is available to save worn or damaged crankcases as 531237. A JIMS breather hole reamer (MCS 978343) will ream the damaged hole to +.030″ so a +.030″ breather can be used.