Oh, these are sweet. I have something similar from REI. They're made out of nylon and very light but perhaps twice the size and probably not as sturdy.
These look perfect for securely connecting small things that you might need to remove in a hurry, e.g., led flashlights. I'm normally gunshy about ordering from little companies on the web I've never heard of, but I'll go with the positive feedback here and give them a chance. Thanks for the pointer!