Rechargeable Li-ion Battery for Cargo GPS Tracker with 7 day standby, 3.7V, 4000mA Rechargeable Li-ion Battery for Cargo GPS Tracker with 7 day standby, 3.7V ... .For more details, please contact our sales department staff. Rechargeable Li-ion Battery for Cargo GPS Tracker with 7 day standby, 3.7V, 4000mA