The product is a lot of 2 GRT01 4000mAh 4 Cell Laptop Battery for Dell Latitude 5421. These black Li-Ion batteries are specifically designed for Dell laptops and have a voltage of 17.8V. With a capacity of 4000mAh and 4 cells, these batteries are compatible with the GRT01 model and the Latitude product line. Made by Dell, these batteries come in a unit quantity of 2 and are ideal for replacing old or worn-out laptop batteries.