This is a momentary button module puls a LED, which helps you find your target in the light. There are Red, Yellow, Blue, Orange and white for you to select. If you have any demand on color, please leave a message when ordering, if not, we will sent you a random color. This module output HIHG when pressed, and logic LOW when released. You can download the Starter Kit Guidebook Experiment 03- Read the Button Input for reference to learn how to use this module.