Need a battery for Panasonic Laptops/Notebooks with the following model numbers: ToughBook CF-29, CF-51, 29, 51 series ? 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 Panasonic part numbers CF-VZSU45, CF-VZSU45U. 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.