1. Boost the voltage of 3.7V lithium battery to 9V or 12V to meet the needs of a variety of equipment. 2. Support 9V and 12V output voltage adjustment, adapt to different application scenarios. 3. Integrated charging and discharging functions, simplify circuit design and improve efficiency. 4. Compact size, easy to install in a variety of portable devices 5. High conversion efficiency, reduce energy loss, enhance the endurance capacity Parameter: Maximum charging current: 1000mA Charging cut-off voltage: 4.2V Battery over-discharge protection voltage: 2.4V Maximum output current: 2A (recommended for use within 1A) Output voltage: 4-12V (adjustable) Caution: The first time you access the battery, there may be no voltage output, you need to charge on the power input to activate the protection circuit. When using a cell phone charger for power supply, it must be to output more than 1A, otherwise it may not charge properly. Color:As Shown Material:Metal+Plastic Package Contents: 1 * Module 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 a little different from the real thing. The measurement allowed error is +/- 1-3cm.