Tri Color Glow Necklaces contain a non-toxic, glow-in-the-dark chemical that illuminates once activated. - To activate, simply bend the necklace until you hear it crack. - Then shake it to really release all the glow throughout the piece. - To attach, connect each end to one another using one of the clear connectors included with each set. Batteries are not required for this product. Specifications: Length: 22.0 in. Width: 0.2 in. Color: Each necklace glows Red, White, and Blue