This is a Lenovo 40Y7001 compatible 4-Cell Li-ion 14.4V 2600mAh 37Wh battery specifically designed for Lenovo notebooks. With up to 2600mAh and 37Wh of power you can rely upon long lasting power be it for work or play. Our batteries mimic the OEM form factor so they fit properly with your notebook. Batteries are 100% tested and compatible with the intended system. Battery life depends on many factors including: available DRAM, screen brightness, applications, features, power management, battery condition and other user preferences. With our certification test program, we can guarantee your product will work right the first time. Our products are also guaranteed by federal law to not affect or void OEM warranties.