Cordless antistatic wrist straps?
These supposedly cordless anti-static wrist straps seem to be very common on eBay. Let's take a look at one.
Dave at EEVblog checked one of these out too:- https://www.youtube.com/watch?v=nvgW5iWXbts&t=0s
It appears to be the equivalent of a scaffolders safety harness. They're wearing it, but it's not attached to anything.
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