Replacement laptop battery for Lenovo ThinkPad T410, T420, T430, T530, W510, W520, W530, L410, L420, and L430 series laptops. Works as a replacement for 70+, 0A36302, 0A36303, 45N1001, 42T4733, 42T4235, 42T4731, 42T4757, 42T4737, and 42T4753. 48Wh rechargeable Li-ion battery designed for compatible Lenovo ThinkPad business laptop systems. Integrated safeguards help protect against overcharge, over-discharge, over-current, and short-circuit conditions. Built for dependable portable power for work, school, travel, and backup use; install after fully powering down the laptop