The Best Tips to Buy Glow Sticks and Bracelets Glow sticks are essentially plastic barrels that hold two liquids, one in the plastic bundling and one inside a glass vial that coasts in the primary liquid. When you contort a glow stick, you break the glass vial which empowers the two liquids to mix. This causes a compound reaction that is bi-thing is light without warmth. The articulation for the reaction is chemiluminescence.