This is the Plyke, an aluminum bicycle bell created by Estonian student Mihkel Annus and photojournalist Martin Pedaja.
It sounds like this:
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The duo says that bike bells typically contain unseen plastic parts, and they claim (without attribution) that "100,000kg of plastic end up in the oceans every year because of bicycle bells." I would love to see where they got that stat.
They also say that "the material carbon footprint of a Plyke bell is 97% less than a bicycle bell with plastic." I dunno though, I'm looking at the shape of this thing, and I assume it's got to be CNC milled or waterjet cut out of a billet. Obviously aluminum can be recycled, but I'm not sure how efficient this is as a production object.
In any case, the €25 ($26) Plyke has been successfully Kickstarted, with 7 days left to pledge at press time.