Bicycle Braking and Turn Signal Light   LED    @Circadea
Automatically  senses braking  via induction.
More information or purchase.
                                                                             Remote Control Version

https://imgaz.staticbg.com/images/oaupload/banggood/images/C4/12/f41be138-35fe-4ffe-b0c2-df89ed545d16.jpgdd
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