Make sure you have ordered the correct battery Dell Battery is available in various models. You can search by battery label number or computer model. I add more model tracking, hope it helps. Ctrl + F to search for models New Replacement Dell T54FJ 8858X M5Y0X Laptop Battery Battery type: Li-ion. Capacity: 4400 mAh. Voltage: 11.1 V. Colour: black. Package includes: 1 x battery. Compatibility list Dell notebook battery: (there should be a model number on the label of the Dell battery). 04NW9 | 05G67C | 2N6MY | 2P2MJ | 312-1163 | 312-1164 | 312-1165 | 312-1242 | 312-1310 | 312-1311 | 312-1324 312-1325 | 312-1439 | 312-1440 | 312-1441 | 312-1442 | 312-1443 | 312-1444 | 312-1445 | 3VJJC | 451-11693 | 451-11693 | 4 51-11 694 | 451-11695 | 451-11696 | 451-11947 | 451-12048 | 4KFGD | 5DN1K | 71R31 | 8858X | 8P3YX | 911MD | 96JC9 | 9844 V6 | CRT6P | DHT0W | GCJ48 | HCJWT | HTX4D | HWR7D | JD0MX | M1Y7N | M5Y0X | N3X1D | NHXVW | P8TC7 | P9TJ0 | PRRRF | PRV1Y | R48V3 | RU485 | TT. 54F3 | T54FJ | UJ499 | WT5WP | X57F1 | YC3PK | YJ02W | YKF0M. Compatibility list Dell computer: (There should be a model number on the bottom of the laptop.) Dell Inspiron Series: 14R 4420 | 14R 5420 | 14R 5425 | 14R 7420 | 14R SE 4420 | 14R SE 5420 | 14R SE 7420 | 14R TURBO | 15R 4520 | 15R 5520 | 15R 5525 | 15R 7520 | 15R SE 4520 | 15R SE 5520 | 15R SE 7520 | 15R TURBO | 15R 5520 SPECIAL EDITION | 15R N5520 | 15R N7520 | 17R 4720 | 1 7R R 572 0 | 17R 7720 | 17R SE 4720 | 17R SE 5720 | 17R SE 7720 | 17R TURBO | 17R N5720 | 17R N7720 | 4420 | 4520 | 4720 | 5420 | 5420 5 | 5 | 5520 | 5525 | 5720 | 7420 | 7520 | 7720 | M421R | M521R | N4420 | N4520 | N4720 | N5420 | N5520 | N5720 | N7420 N75 N7520 | N7720 Dell Latitude Series: E5420 ATG | E5420 N-Series | E5420 | E5420M | E5430 | E5520 BRC | E5520 N-Series | E5520 | E5520M | E5530 | E6420 ATG | EE64200XFR | E6420 | E6430 ATG | E6430 | E6440 | E6520 | E6530 | E6540. Dell Precision Series: M2800 Mobile WorkStation | M2800 Dell Vostro Series: 3460 | 3560. Buy with confidence! 100% new from Pro manufacturer. Good quality. More professional 12-month warranty