HWG T420S Battery (6-Cell) for Lenovo T420S T420Si 0A36287 42T4844 42T4845 42T4846 42T4847 45N1036 45N1037 Battery type: Li-ion; Voltage: 11.1V; Capacity: 3600mAh; Cells: 6-cell; Color: Black Compatible Models: Lenovo ThinkPad T420S, T420Si, 0A36287, 42T4844, 42T4845, 42T4846, 42T4847, 45N1036, 45N1037 etc. Series. 100% New from Manufacturer. Up to 500 recharge cycles over the life of the battery. Grade A cells ensure fast charges and low power consumption. Every battery has passed factory testing; Durable grade A cells battery; Quality assurance. 24 x 7 email support; 12-month hassle-free warranty. Fulfilled by Amazon.