Voltage Measurement: Equipped with an LED voltmeter, this DC-DC Buck Converter offers precise voltage readings with a minimal error margin of ±0.1V. The voltmeter can be easily toggled on and off, allowing real-time voltage monitoring or power conservation when not in use. Wide Input and Output Range: This adjustable buck converter supports an input voltage range of 4V to 40V and an output voltage range of 1.25V to 37V, suitable for various applications including DIY electronics and industrial use. Efficient Power Regulation: Featuring an internal oscillation frequency of 150kHz, the converter ensures low power consumption while maintaining high efficiency. Solid capacitors enhance circuit stability, durability, and high-frequency noise filtering. User-Friendly Interface: The onboard voltmeter operates only when the input voltage is 4V or higher, ensuring reliable readings. A simple press-and-hold mechanism enables easy control of the voltmeter display. Color: As Shown Material: PCB + Components Package Contents: 4 x DC-DC Buck Converter Note: Light reflection and display differences may cause slight color variation between the image and the actual product. Measurement tolerance is ±1–3cm.