Overview

This is a very simple little tool that I've nonetheless found incredibly useful for breadboard prototyping! It's a little stick with two pins, spaced the standard 0.1"/2.54mm, marked + and -, with LEDs in opposite polarities. When current flows from + to -, the green LED lights up. When it flows the other way, the red LED lights up. Nifty!

This version has LEDs and +/- markings on both sides, making it a bit easier to see from every angle. I also sell a single-sided polarity stick, which is a little cheaper and will draw less current from your circuit.

Handy for all kinds of quick-and-dirty testing! I use these to double-check that I've hooked up the power rails on our breadboards correctly, as indicators for microcontroller projects (no need to worry about adding a resistor!), to test reverse voltage protection circuits, and more.

It can take up to around 12V in either direction (but will light up with as low as 3.3V).

Includes 1 stick.