Features: 3.7V USB battery charging cable with 51005 connectors. The charging cable is equipped with an intelligent charging management chip, which can accurately charge the 3.7V lithium battery, automatically stop when fully charged, without overcharging. The cut-off voltage when fully charged is 4.23V, which means that the characteristics of lithium batteries are reasonably utilized to better extend their lifespan. Charging indicator: When USB is connected, there is no indicator light. When the battery is connected for charging, the red light is on, and when it is fully charged, the red light is off. Applications: Polymer lithium batteries, cylindrical lithium batteries, digital lithium batteries, lithium batteries for remote control aircraft. Specifications: Name: 3.7V USB charging cable Material: plastic Black color Protection function: overcharge protection Application: Lithium battery charging Output parameter: 3.7V 500mA Speed power: 2-5W Connectors Model: white 2.0mm 51005 connectors Input voltages: DC5V 0.5-2A Output voltages: DC4.2V 500mA Note: Please allow 1-2cm errors due to manual measurement. Please allow slight color difference due to different display resolutions. Package includes: 1x USB charging cable