Specification: Origin: Mainland China Input voltage: 12V Output voltage: nominal 3.7V full stop voltage 4.2V lithium battery single series lithium battery charging management Interface: 2Pin PH2.0/JST Product weight: 7g Product size: About 45 * 20 * 9.5mm/1.77 * 0.78 * 0.37inch Tips: This module has three input voltages of 12V, corresponding to the working voltage (nominal voltage) of the solar panel of 12V. The CN3791 MPPT Solar Charger 12V should be paired with a solar panel with a working voltage of 12V. Note: Due to the different monitor and light effect, the actual color of the item might be slightly different from the color showed on the pictures. Thank you! Please allow 1-2cm measuring deviation due to manual measurement. Included: 1 x Charging Module 1. Maximum Power Point Tracking (MPPT) Solar Charge Controller: The MPPT solar charger allows you to get the maximum amount of energy from your solar panel or photovoltaic device and store it in a rechargeable lithium battery. 2. Easy to Use: Simply plug the solar panel into one side of the solar charger and the battery into the other side to start charging. 3. Automatic MPPT Functionality: The CN3791 power tracking battery charging circuit can automatically track the maximum power point of the solar panel even as light conditions change, allowing you to maximize the output of your solar panel without worrying about worst-case scenarios. 4. Comprehensive Battery Charging Management: The solar charger is designed to charge individual polymer lithium-ion batteries with a load that is parallel to the battery. It comes with four 2-pin JST/PH2.0 connectors already installed.