NinjaBatt Battery for Dell XCMRD MR90Y 3521 15-3521 FW1MN 3540 3531 15-3531 15R 5537 3440 15R-5537 3542 4DMNG V8VNT 3443 5737 49VTP 24DRM 312-1387 312-1433 451-12107 451-12108 – 6 Cells/4400mAh