Alliboo 11.1V 56WH Laptop Battery for Dell Inspiron 14 14R 3421 5421 5437, 15 15R 3521 5521 5537, 17 17R 3721 3737 5721 5737, Latitude 3440 3540, Vostro 2421 2521-12 Months Warranty Battery Type: Li-ion; Voltage: 11.1V; Capacity: 5200mAh/56WH; 6 Cell. 100% New from Manufacturer; High Performance N3421 3521 Replacement Battery. Overcharger and Discharger Circuit Protection; CE-/FCC-/RoHS-Certified for safety. Contain with Durable cells; Low power consumption IC design; Tested with strict quality control standards; Direct warranty from Manufacturer. Warranty: 12 Months Warranty, 30 days money return guarantee; 24 x 7 email support.