500 UV Multi Color Changing Reactive Plastic Pony Beads Official Cosmic Crafts Brand. Makes great craft projects! 7 Assorted Colors: Rose, Orange, Yellow, Fuchsia, Blue, Indigo, Violet Comes with (5)-1 meter stretch strings to make UV detecting bracelets, necklaces, keychains and so on Made into curtain, it will change color and decorate the window. Looks cool. Size: 9mm in diameter, 6mm in high, 3mm hole in the middle