Romisen RC-C8 CREE Q5-WC 3-Mode 210-Lumen Convex Lens LED Flashlight (1*18650/2*CR123A/3*AAA)

I did replace the lens with the 28mm glass convex SKU 5297 (and NOT 5927) as someone else suggested. It makes sense as the glass clearly transmits visibly more light compared to the standard plastic. However, I didn't find the focal characteristics of the 5297 very pleasing, since for a significant part of the flood-to-throw adjustment run (at least for the distance and throw one needs for a bicycle), it produced a very bright, clear and concentrated image of the LED with little light escaping in the flood. This makes for a very unequal, not very 'enlightening' and, frankly, quite distracting spot. I think I'll sacrifice some brightness and stick with the plastic lens until I figure out something else.