1. Features a voltmeter display with a 0.1V measurement accuracy, operating range from 5V to 35V. (Note: the onboard voltmeter will not function or display if input voltage is below 4.5V) 2. Press the button to toggle between input and output voltage measurement. An indicator light shows which voltage is being measured. Upon initial power-on, the digital display defaults to input voltage with the IN indicator lit. Pressing the button switches to output voltage display with the OUT indicator lit. The module retains the last selected mode even after power cycling. 3. The voltmeter can be turned off by pressing the switch for more than 1 second but less than 4 seconds, then releasing. To reactivate, simply press the button briefly. 4. Equipped with terminal blocks for easy wiring without soldering. Connection points are provided. (Input voltage must be at least 1V higher than output voltage) 5. Maximum output current up to 3A; recommended operating current is approximately 2A. A heatsink is recommended when exceeding 2A. 6. Utilizes a 400kHz internal oscillation frequency, part of the second-generation switching regulator technology, offering low power consumption and high efficiency. 7. Suitable for boost applications where output voltage exceeds input voltage, such as battery systems, power supplies, DIY adjustable voltage regulators, 24V vehicle-mounted notebook adapters, industrial equipment voltage conversion, 9V to 12V, 12V to 18V, 18V to 24V, and similar applications. Input voltage range: 4.5V to 32V Output voltage range: 5V to 35V (adjustable) Maximum input current: 4A Note: Minor variations in silkscreen or appearance may occur between batches, but do not affect functionality. Color: Blue Material: PCB + Electronic Components Package Contents: 2 x XL6009 DC-DC Boost Module The package includes only the items listed above; other accessories are not included. Note: Lighting conditions and monitor settings may cause slight color variations between the product image and actual item. Measurement tolerance is +/- 1-3cm.