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, ensuring you can monitor your voltage settings in real-time or conserve power when needed. Wide Input and Output Range: Catering to a broad spectrum of electrical applications, this adjustable buck converter supports an input voltage from 4V up to 40V and an output voltage range from 1.25V to 37V. This flexibility allows for various uses from DIY electronics to industrial applications. Efficient Power Regulation: Featuring an internal oscillation frequency of 150KHz, the converter ensures low power consumption while maintaining high efficiency. The integration of solid capacitors enhances circuit stability and durability while effectively filtering high-frequency noise. User-Friendly Interface: The onboard voltmeter of the not operate if the input voltage falls below 4V, ensuring reliable readings. A simple -and-hold mechanism allows for effortless control over the voltmeter display, making it user-friendly and accessible. Color: As Shown Material: PCB+Components Package Contents: 4 Pack DC-DC Buck Converter 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.