This particular prop was something one of our actors was wearing. In a particular scene they start to glow, but for it to look any good they needed to cast a light that interacts with their surroundings.
The way it worked as I ran wires through out and hid some connectors in the seams, so that I could attach LED strips to the blindside to the camera, this allowed for a flexible rig. Could run of a 12v wall wart or battery if needed.
This rig didn’t get as much screen time as I’d have liked ended up casting across a pretty featureless wall. Still, I got to flex those sewing muscles (and by flex I mean flinch as I kept sticking myself)