Review on 🚴 Padonow Smart Bike Tail Light: Auto On/Off Flashing Red LED Lights, Easy Mount Cycling Safety Brake Taillight - USB Rechargeable, Ultra Bright, Light Sensing Bicycle Rear Light by Patrick Cooney

I bought this ($26) and returned it immediately as it wasn't bright enough for daylight use. When asked about the brightness, the seller said "35-40 lm" in flashing mode. The description of the listing also says "high luminous flux", visible during the day and "super bright". Actually, it's none of them. I tested it (after a full charge) with my old Planet Bike Blinky 3 (4 lumens) by looking at them from 50-75 meters away in daylight. I could tell Blinky 3 was on, but I couldn't tell the Padanow light was on until I was about halfway up. The light looks nice and should work well in night light but definitely not in broad daylight. I've tried to show the relative brightness with the attached images and videos, but the camera doesn't really show much of a difference in brightness. The aluminum bracket feels solid and is easy to install. The problem is that it has to be installed on the seat so that the rails are parallel to the floor, otherwise the light will be directed towards the floor. With my bike it took about half the length to set it up and tilt the seat slightly to get it level. I didn't like adjusting the seat for the light. I ended up buying the Planet Bike Grateful Red USB ($28, 20lm flash) and it was way brighter than the other two.