Four digit digital voltage readout

This listing is for a 0-20VDC Digital voltage display. They are extremely accurate and are rated for a +/- 1% tolerance of error. There are two pins on each side. If you look at the second picture, there is a basic schematic. The bottom left and right side pins are ground pins. The left side requires 7-14VDC to power. A 9v Battery works great. They have a low power consumption, so an Energizer battery will work for a long time! The right side is the reference side. Once you have applied power to the left hand side, you can place any voltage between 0VDC and 20VDC. If you leave the reference input floating, the read-out will display 00.00v. In the first picture, you may notice that I implemented one into one of my own projects (a SUPER capacitor charger). If you are interested, or have any questions, please feel free to ask!