Bull 9 Cell 55+ New Laptop Battery Replacement for Lenovo Thinkpad E40 E50 0578 E420 E425 E520 L410 L420 L510 L520 Sl410 Sl510 T410 T420 T510 T520 W510 W520, Replace for FRU 42t4751 42t4755 Battery type:Li-ion ; Voltage:11.1V ; Capacity:73WH; Color:Black Fit laptop models:Thinkpad E40 E50 E420 E425 E520 E525 Edge,Lenovo IBM ThinkPad SL410 SL410k SL510 T410 T420 E420 T510 T510i T520 T520i W510 W520 Compatible P/N:42T4708 42T4709 42T4710 42T4712 42T4714 100% New from Manufacturer. Up to 500 recharge cycles over the life of the battery. Warranty: 12 Months Warranty,30 days money return guarantee!