Maxima Performance Break-in Oil is specifically designed for breaking in engines with flat tappet camshafts, roller elements or where elevated levels of anti-wear additives are needed. High Zinc / Phosphorous formula is blended with highly refined, pure petroleum base stocks to provide optimum ring seal. Usage: Not Recommended For Street Use. Maxima Performance Break-in Oil formula has elevated anti-wear additives designed to protect engines in extreme conditions. Elevated anti-wear additives may adversely impact emissions systems on vehicle. For use in the break-in of high performance race engines, including Off-Road, Circle Track, Drag, etc. Promotes ring seal and provides maximum protection for cams and all critical valve train components during initial break-in of flat tappet and roller cam engines. Compatible with petroleum, semi-synthetic and fully synthetic motor oils.