Waterproof Mini DC-DC Step-Down Converter 12V to 5V/9V Buck

$9.73 $12.19

Color 9V 3.3V 3.7V 4.2V 5V 6V

Waterproof Mini DC-DC Step-Down Voltage Converter – 12V to 3.3V / 3.7V / 4.2V / 5V / 6V / 9V

Keep your electronics powered exactly how they need to be with this compact, waterproof DC-DC step-down voltage converter. Designed for car, automotive, marine, and DIY electronics applications, this buck converter efficiently reduces a 12V DC input to your choice of output voltage — 3.3V, 3.7V, 4.2V, 5V, 6V, or 9V — making it ideal for powering microcontrollers, sensors, LEDs, radios, and other low-voltage devices directly from a 12V source.

Its rugged plastic and metal construction combined with a waterproof design makes it a reliable choice for under-the-dash automotive installs, outdoor electronics projects, and marine environments where moisture is a concern.

Key Features

Wide Output Voltage Selection: Supports 3.3V, 3.7V, 4.2V, 5V, 6V, and 9V output — compatible with a wide range of electronic components
Waterproof Design: Sealed housing protects internal circuitry from moisture, dust, and splashes
Compact & Lightweight: Measures just 4.6 × 2.8 × 1.4 cm — fits easily in tight spaces
Plastic Shell + Metal Construction: Durable build for long-lasting, reliable performance
Simple Wiring: Color-coded leads for easy connection (Red = Input+, Black = Input−, Yellow = Output+)
Efficient Step-Down Conversion: Minimizes energy loss for stable, consistent power delivery

Specifications

Type: DC-DC Step-Down (Buck) Converter
Input Voltage: 12V DC
Output Voltage Options: 3.3V / 3.7V / 4.2V / 5V / 6V / 9V
Material: Plastic shell + Metal
Dimensions: 4.6 × 2.8 × 1.4 cm
Wiring: Input: Red (+) / Black (−) | Output: Yellow (+) / Black (−)
Package Contents: 1 × DC-DC Step-Down Converter
Country of Origin: Made in China

Perfect For

Automotive electronics and car audio installs
Arduino, Raspberry Pi, and microcontroller projects
Marine and outdoor waterproof wiring setups
LED lighting circuits
DIY electronics and hobbyist projects

Frequently Asked Questions

Q: What input voltage does this DC-DC step-down converter require?

A: This converter is designed to work with a 12V DC input, making it ideal for use in cars, trucks, and other 12V battery systems. It then steps the voltage down to your chosen output level.

Q: What output voltages are available with this converter?

A: The converter is available in multiple output voltage options: 3.3V, 3.7V, 4.2V, 5V, 6V, and 9V. Please select the desired output voltage before purchasing to ensure compatibility with your project.

Q: Is this converter truly waterproof for outdoor or automotive use?

A: Yes — the unit features a sealed waterproof housing made from a combination of plastic and metal, offering protection against moisture, splashes, and dust. It is well suited for automotive, marine, and outdoor electronics installations.

Q: How do I wire this step-down converter?

A: Wiring is straightforward and color-coded. Connect the Red cable to your positive 12V input, the Black cable to your negative/ground input, and use the Yellow cable for your positive output. The second Black cable serves as the output ground.

Production & Packaging Notice

To maintain high stock availability and fast shipping times, our items are sourced from multiple verified manufacturing facilities. While the core quality, materials, and product specifications remain identical, you may notice slight variations in the packaging design, manufacturing origin, or the wording of the printed instructions.