Maximal Power LB Dell Ins D1520 Replacement Laptop Battery for Dell Inspiron 1500, 1520, 1521, 1720, 1721, and e1520 Series (Black) 5200 MAH 6 Cell Li-ion battery 100% Compatible with original manufacturer equipments and chargers Maximalpower Brand is one of top selling brands for replacement batteries at amazon.com for Straight three years backed with 1 year warranty and $1 million product liability coverage Integrated microchip prevents overcharging and lengthens battery life