Brand new and high quality Features: Start the first phase of constant current charging, the LED indicator is red, when the charging reaches the rated voltage, switch to the second phase constant voltage charging, the current slowly decreases, when the charging current reaches the reverse current, the LED indicator lights up green. At this point, the battery has been fully charged to 90%-95%, and the battery continues to charge with a small current until it is full. Overvoltage protection Overcurrent protection Use constant current and constant voltage charging mode, full Stop. (Lead-acid battery charges in three stages) Used for charging lead-acid battery packs, lithium-ion battery packs and nickel-hydrogen battery packs. Set the charging parameters according to the charging characteristics of the battery pack. (Note that it has been set at the factory) Use two-color indicator light, red light during charging, empty or full of this green light. Specification: Max. Power: 84W Input voltage: 100-240V AC Max. output voltage: 42V Max. output current: 2A Line frequency: 50-60Hz Efficiency (at load): >=85% Ripple: <=1%*Vo Temperature range: 0-45''C Relative humidity: <65% Size: 13x5x3cm (5.3x1.2in) Notes: 1. The color deviation may be different due to different monitor settings. 2. We provide you with the best product and service, if you have any problem, please let us know, we will solve the problem as soon as possible. Thank you very much. Package includes: 1XPower adapter