43121 Opti-4 engine oil 34 oz, Opti-4 Premium Engine Oils 4 cycle power equipment.
Interlube stands behind Opti-4 to the point of doubling the engine warranty of the engine that uses Opti-4 oil. All purchasers of new equipment that is initially serviced with Opti-4 and continues to use Opti-4 oil, Interlube will carry the second half of your doubled engine warranty. If you have a 2 year engine warranty, they will cover an additional 2 years to extend your warranty period to 4 years.