Need a battery for Lenovo-IBM Laptops/Notebooks with the following model numbers: ThinkPad T40, T41, T42, R50, R50E, R50P, R51, R52 ? 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 Lenovo-IBM part numbers U3-130,28-390,BQC-PGM10X//1,L129,LA300,LCA3113,LCA3119,LMP-M130,LT50LP,LT51LP,U3-130,VLT-X30LP,VLT-XD20LP. 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.