Having ridden using this SRAM Red rear derailleur for years it unfortunately stopped working. When I pressed the button a yellow light did come on. However, I did manage to get it working again only for it to stop. Took it to my local bike magician and he confirmed it was done which was not the news I wanted. So this is spares only. There is unfortunately no battery. Any questions please reach out. Thank you for taking the time to read.
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