New SL410 Laptop Battery for Lenovo ThinkPad/IBM E40 T420 L410 T410 L412 L420 E50 W520 E525 L510 L520 Sl510 T510 T520 W510，Fit P/N FRU 42T4751 ASM 42T4752 42T4751 42T4791 51J0499 42T4235

hi this is Sarah Dubois with laptop battery express this 6l Lenovo battery is rated at 4,400 milliamp hours or 48 watt hours and will give you about two to three hours of runtime depending on your energy use the mah or milliamp hour and the whr or wat our indicates how long a battery will run on a charge the higher the milliamp hour and wat our number the longer the battery will run all of our batteries are brand new with Samsung Power Cells a Texas Instruments computer chip and are never used or refurbished if you're finding less expensive batteries on line please be aware that it's because they use cheap quality power cells inside the cartridge that can easily wear out in six months our batteries typically have a service life of three to five years all batteries from laptop battery Express come with a 30 day money back gaurantee and a full 12 month warranty all of our batteries ship f