This little lightweight French rear light from the late 30's to 40's has been converted with a convenient UNION usb plug in LED light that runs for 4 hours 15 mins on full charge flashing mode. You can find another on ebay for back up.
Brass bracket that I made bolts on to your seat stay. The period faceted lens is great and sends out a bright light.
Shipping England & Wales Tracked £4.99