TAUPO Laptop Battery for Lenovo ThinkPad E40 E50 L410 L420 L510 L520 L412 L412 SL410 SL510 T410 T420 T510 T520 W510 W520, ThinkPad Edge 14 15 E420 E425 E520 E525, fits P/N 57Y4186 42T4791 51J0499 Battery type: Li-ion; 6-cell; Capacity: 4400mAh/48Wh; Voltage: 10.8V Replace Part Numbers: 42T4708 FRU 42T4702 FRU 42T4753 FRU 42T4793 FRU 42T4795 FRU 42T4797 FRU 42T4803 FRU 42T4817 FRU 42T4819 FRU 42T4791 Grade A cells ensure fast charges and low power consumption; Built-in circuit protection ensures both safety and stability 100% New from Manufacturer. Up to 500 recharge cycles over the life of the battery CE-/FCC-/RoHS certificated for safety, 12 months warranty, professional technical support, efficient and always satisfied customer service, 24 x 7 email support