Need a battery for Asus Laptops/Notebooks with the following model numbers: G50, G60, G71, L50, M50, M51, X55 (9-cells)? BTI has you covered with our premium 9 cell LiIon battery. This product has been engineered to meet or exceed the original manufacturer's specifications and replaces the original Asus part numbers A33-M50, AS A2NYAS11274407A. All BTI batteries are manufactured and tested under our stringent quality standards and come with an industry leading 18 month manufacturer's warranty. BTI... True to the original.