S&S OIL FILTERSS&S OIL FILTERS Canister is slightly smaller in diameter than stock filters to make them easier to remove and install Designed with a direct bypass valve that routes bypass oil directly to the filter exit, which minimizes the amount of contaminants carried to the engine in the unfiltered bypass oil The nominal particle capture size is smaller than that of stock filters while the resistance to oil flow is nearly the same Made in the U. S. A. Sold each