Features 1、Can protect batterys and prolong the service life of batterys. 2、Used for Charging/discharging four groups of lithium batterys in series. 3、Each group can connect multiple lithium batterys in parallel. 4、Applicable to the nominal voltage of 3.7V, fully charged 4.2V lithium batterys, can be drilled below 170W. Specification Features: Can protect batterys and prolong the service life of batterys. Used to Charging/discharge four groups of lithium batterys in series. Each group can connect multiple lithium batterys in parallel. Applicable to the nominal voltage of 3.7V, fully charged 4.2V lithium batterys, can be drilled below 170W. Specifications: Version: Enhance Charging-Voltage: D C16.8-17V Continuous Charging-Current: up to 20A Continuous Discharge Current: 40A Maximum (Nice heat dissipation condition) Item Size: 55 * 44 * 4mm / 2.16 * 1.73 * 0.16in Package Size: 120 * 80 * 12mm / 4.72 * 3.15 * 4.72in Package Weight: 10g / 0.35ounces Package List: 1 * Protective Board Package List 1 * Protective Board