This is a set of two unbranded/generic laptop batteries compatible with Dell Inspiron and Vostro laptops. They have a battery capacity of 40Wh and a voltage of 14.8V with four battery cells. The batteries are compatible with specific Dell Inspiron models such as 3451, 5451, 5551, 5555, 5558, and 5559. The product comes with a manufacturer warranty of five years.