New aftermarket laptop replacement battery 10.8V 57Wh 6 cell Replaces Part #'s 42T4751, 42T4753, 42T4755, 42T4757, 42T4791, 42T4793, 42T4795, 42T4797, 42T4848, 42T4852, 42T4911, 42T4921, 42T4923, 42T4925, 42T4927, 45N1001, 45N1003, 45N1005 Works w/ Lenovo Edge 15, Lenovo ThinkPad L421, L520, SL410, SL510, T410, T410i, T420, T420i, T430, T510, T510i, T520, W510, W520, Lenovo ThinkPad Edge E420, E425, E520, E525 Laptops