Need a battery for Asus Laptops/Notebooks with the following model numbers: F70SL, G71, G71G, G72Gx, M70, M70S, M70V, N70Sv, N90, N90Sv, X71SL, X71Vn? BTI has you covered with our premium 8 cell LiIon battery. This product has been engineered to meet or exceed the original manufacturer's specifications and replaces the original Asus part numbers 70-NA51B2100, 90-NA51B2000, 90-NA51B2100, 90-NA51B2200, 90-NA52B2000, 90-NA71B1100, A42-A3, A42-A6. 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.