Time marches on and generally that's a good thing. But unfortunately, over time, some of the good stuff can get left behind. COMP Cams Engine Break-In Oil Additive brings back the good stuff, delivering a specially engineered blend of extreme pressure break-in additives that have been removed from current off-the-shelf motor oils. Delivering added protection during the break-in process and beyond for all engine components, including the camshaft and lifters, COMP Cams Engine Break-in Oil Additive is compatible with any petroleum, synthetic or blended motor oil.COMP Cams Engine Break-In Oil Additive extends the durability of internal engine components, protecting against premature camshaft, lifter and valve train failure. Best of all, COMP Cams Engine Break-In Oil Additive has proven to deliver long term benefits with new or rebuilt engines through continued usage. Simply pour in a bottle for initial break-in, run the engine for approximately 1,000 miles, drain the system thoroughly and then refill with clean oil and another bottle of COMP Cams Engine Break-In Oil Additive at each oil change.