Advanced Charging Management: Equipped with a high-end MPPT technology chip, this solar panel controller ensures optimal power tracking. Premium Components for Reliability: Utilizes top-grade components including high-frequency low-conductance dual MOS tubes, high-current diodes, and high-efficiency flat high-power inductors. Enhanced Heat Dissipation: The controller is designed with a large-sized aluminum heat sink at the base, promoting excellent heat dissipation. Efficient and Rapid Charging: This solar panel controller is engineered for high-speed and efficient charging, minimizing heat generation and maximizing charging speed. Intuitive Dual Status Indicator: Features a dual status indicator light system for easy monitoring. Input voltage: nominal 18V solar panel (no-load 21V or so solar panel) Output voltage: nominal 12V (10.8–11.1V), full charge cut-off voltage 12.6V, compatible with 3-series lithium battery charging Output current: maximum constant current 3A (charge current 2A; additional heat dissipation recommended) Wiring method: solder pad IN+ input positive pole, IN- input negative pole (SOLAR) BAT+ battery positive pole, BAT- battery negative pole Due to different batches, there may be differences in product appearance and printed text, which do not affect use Color: Red Material: Plastic Package Contents: 2 x MPPT Solar Panel Controller Only the above package content, other products are not included Note: Light reflection and different displays may cause the color of the item in the picture to be slightly different from the real thing. The measurement allowed error is +/- 1-3cm.