From the manufacturer:
Add color for decoration or to blend in with your project. These colored glue sticks are safer-to-use adhesives are perfect for securing delicate materials that bond best with lower-temperature glue. Easy to install into gun, handle and clean up after use. Not every project calls or allows for sizzling hot glue and our Cool Shot formula solves this problem without sacrificing performance. Our specially designed formula melts at a lower temperature than traditional hot glue but flows and adheres just as well. Colors included red, orange, yellow, green and blue.