Glow-in-the-dark; CLEAR- Cosmo Beads(tm) Water Balls; 10g pack by Cosmo Beads Glow-In-The-Dark COSMO BEADS! A novelty item for kids of all ages. Simple directions make them ideal for anyone to use; the young/elderly. Yup, they glow in the dark by placing them under direct sunlight or light source in the room for 5-7 hours before or after hydration. The longer exposed to light the longer they'll glow. MULTIPURPOSE: Deco Centerpiece; Toy-games Hours of educational fun for kids. Harvest Size: 10 grams of Glow-In-The-Dark COSMO BEADS Under maximum hydration (10 hrs.) will yield about 5-6 cups of round bouncy GLOW-IN-THE -DARK crystal water beads. Reusable up to 2 years, Non-fade, Non-Toxic, 100% Biodegradable, Non-Flammable.