Creating a light visible in the daylight requires intentional design. By directing or amplifying output, we intensify the beam or extend its range. Without this, a light may appear bright, but will not be noticed in the day.
Most tail lights use a steady flashing pattern. This pulsing is less noticeable than one that continually varies its intensity and pattern. The Day Flash setting featured on Bontrager Daytime Running Lights was created to specifically increase noticeability with varying outputs and an interruptive flash pattern.
Daytime Running Lights are brighter than what you would use at night in order to give drivers more reaction time. Bontrager Daytime Running Lights are detectable from a greater distance than other lights, from ¼ mile to over 2km away in daylight conditions given the specific model.