Put a voltage meter anywhere with this very handy display. These are often used by RC hobbyists for keeping track of batteries but we thought it would be great on a breadboard or enclosure.
Simply connect the red wire to the positive supply, and black to negative ground. The display has a microcontroller that will read the voltage, compare it to a stable reference and display the voltage with 0.1V precision on a 3-digit 7-segment display. It works from 3.2V up to 30V so it will be good for nearly any electronic project! The meter draws 3-4mA to power the microcontroller and display. This particular LED display is a nice vivid green, which we found very readable. Mounting tabs make this module easy to attach to any box or plate. [via]
Mini Volt Meter - [Link]