I did the Light and Motion Vis 180 LED rechargeable tail light, $50-$80, eBay-Amazon:
https://www.amazon.com/Light-Motion...2624&sr=8-1&keywords=light+and+motion+vis+180
I have the Topeak fat tire rack; but, it has the same mounting point for a light like the Radrover rack. I use the 70 lumen light day and night because it is so bright. It has a solid light (4hrs) solid high pulse (6hrs), or low pulse (12hrs) blink rate instead of the fast strobe most lights have. It also has a yellow light only follow feature (32hrs) for night rides so you don't night blind riders behind you on a bike path.
I mounted the light sideways and I put a few extra zip ties around the light to keep it from walking off. I use the light about 1-3 hours a day depending if I go straight home or trial ride before heading home after work. I have 4-foot retractable mini
USB cable, Amazon, $9, I keep in the rack bag if I need to recharge the light at home, work, or from the bike (usually just recharge 1-2 times a week in garage).
I tried the Vis 180 Micro to mount on the back of my helmet. I ended up getting shipped back/forth 3 replacements because the power button on Micro would take 5-10 times to turn on or off. Zero problems with larger size Vis 180 power button. Found two more units on eBay for about $55 each (2nd Radrover and back of my helmet).
You can see the Vis 180 mounted under the Topeak Rack bag on Radrover near hatch on 2nd picture.
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