Runnerway New Replacement Laptop Battery for Dell Inspiron 14-3421, 14R-5421, 14R-5437, 15-3521, 15R-5521, 15R-5537, 17-3721, 17-3737, 17R-5721, 17R-5737, Latitude 3440 3540, Vostro 2421 2521 Battery Type: Li-ion; Voltage: 11.1V; Capacity: 4400mAh; Cells: 6 Cell All Runnerway products are Certified by CE, FCC for safety. Strict guidelines for compatibility, and standards compliance for environment safety Contain with Durable cells; Low power consumption IC design; Tested with strict quality control standards Compatibility: Compatible with Dell Inspiron 14 14R 15 15R 17 17R Latitude 3440 3540 Dell Vostro 2421 2521 (Please see more in our product description) 12 months warranty and 24 x 7 Email Support, any questions please feel free to contact us