headlight? rechargeable, how? USB internal battery ?

Or Removable flashlight batteries , which themselves are rechargeable?

I don't know what you will find, in Greece, some brands are importer's names, and vary by importer, to that country..

SJS in UK has PDW and CatEye. those are made in Asia.. we get hem in USA.

here is their sorting of USB lights; https://www.sjscycles.co.uk/lighting...-self-powered/
The German stuff won't offer a flash option..

A Xenon bulb flashes very brightly , LED less so..





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