Love that!! I bet it’s only visible in the pitch dark though, rendering it somewhat useless. I really really WANT to like fiber optics but am too much of a brightness fiend to settle for “faintly glowing” costumes.
Actually, they are as bright as the LED you put on them. And depending on what type of fiber optics you use, you can either have just the ends light up, or the sidewall. They’re pretty cool to play with.