Usage Tips: 7.4V SM4P Reverse Charger 4-pin Lithium Battery USB Reverse Charging Cable Walkbee Features: - and high quality - SM4P 400mA output current, 7.4V (3.7V x2) output voltage - Automatically adapts to USB input power, quickly and stably recharges the battery - USB charger with SM-4P plug for Li-ion battery, compatible with electric RC toys, cars, boats, and other USB chargeable devices - Correct positive/negative connection between the charger and battery must be confirmed before use - Built-in intelligent load identification chip prevents excessive current and voltage from entering, protecting the device from damage Specifications: - Item: USB Li-ion Battery Charging Cable - Input: DC 5V - Output Voltage: 7.4V (3.7V x2) - Output Current: 400mA - Adapter Length: Approx. 63mm / 2.47in Notes: - Before ordering, please confirm the positive and negative terminals of your battery plug - Allow 0–1cm error due to manual measurement; ensure you are comfortable with this before purchasing - Due to monitor differences, the image may not reflect the actual color of the item Package Includes: 1 x Battery Charger