Do you want to make your roads safer and more friendly? Then you need a SID - a Speed Indicator Device. A SID is a device that displays the speed of passing vehicles and gives feedback with a smiley or a sad face. One of the most popular SIDs is the TruSign Smiley SID, which is easy to install, portable and can even run on solar-power. Read on to learn more about the benefits of using a Smiley SID and how to get one for your community or workplace. Make a difference with a Smiley SID