If it's going on the seat stay I'd stick one (or a fibre flare or cheapo one or something) on the opposite stay as well for maximum visibility. At some points your wheel or the bag is likely to block it.
@aggi started
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If it's going on the seat stay I'd stick one (or a fibre flare or cheapo one or something) on the opposite stay as well for maximum visibility. At some points your wheel or the bag is likely to block it.