HPR 10 is a premium, full synthetic SAE 10W-50 engine oil. It features a DOUBLE LAYER of engine wear protection with FULL ZINC and Penrite's advanced EXTRA TEN technology. It uses a combination of the latest additive technology and a low shear rate viscosity modifier, to ensure additional protection against wear, corrosion, oil oxidation, piston deposits and sludge under all conditions. HPR 10 exceeds the latest API SN/CF requirements, as well as many manufacturers' specifications.