I still don't understand why some of you think it's so important to use tailight (and some also using headlight) in bright day time, like it's better than hi-viz clothing. Is a small flashing taillight really more noticeable by drivers than large sized hi-viz clothing/bag? Any drivers can share opinions?
There are plenty of lights that are VERY visible in daylight hours.
I also wonder why people bother to run cheap, dim lights in daylight hours. That's just pointless. But I have been told by a number of people that they can see my flashing headlight (Cygolite Expilion 700), and taillights (dual Cygolite Hotshots), from as much as a mile away even during daylight hours. That's going to alert motorists of my presence far earlier than high-vis stuff will.