DELL RJ40G 15.2V 63Wh 4-Cell Notebook Battery For DELL Latitude 5420, Latitude 5520, Precision 3560 Series Laptops P/N: P137G P137G001 P104F P104F001 P104F002 075X16 01K2CF 0WK3F1 0M3KCN 005R42

Battery Information: 4-Cell Premium OEM Quality, Voltage and Capacity: 15.2V 63Wh. Note: There are two battery models (4 Cell 63Wh --- RJ40G and 3 Cell 42Wh --- WY9DX) available for the DELL Latitude 5420 and DELL Latitude 5520 laptop. Please select the correct one based on your laptop's original battery. If the new battery is not detected during initial installation, please reinstall and ensure the connection interface is fully seated. Discharge the new battery to 10-20% (not 0%), then charge and discharge it 3-4 times to condition the new battery. Certified Security: 100% Brand New from the manufacturer. Features protection against overcharge, overdischarge, over-temperature, and short-circuit; Rated for up to 500 recharge cycles. Package Contents: 1 Brand New OEM Battery. Compatible with DELL Latitude 5420 and DELL Latitude 5520