Wide Glow Bracelets contain a non-toxic, glow-in-the-dark chemical that illuminates once activated. To activate, simply bend the bracelet until you hear it crack. This will release the chemical from within the glow bracelet and it will immediately start to GLOW! Each Bracelet is 8 inches in length and attaches using the provided connectors. Dimensions: Length: 8.0 in. Width: 0.5 in.NOTE: These are sold in packs of 25 only, so when you purchase a quantity of 2 you will receive 50 Glow Bracelets and so on. Batteries: Batteries are not required for this product.