The Solar Storm X2 is a good and frequently used bicycle lamp, but it is so strong that it blinds the opposite traffic.This limiter cuts the unnecessary, blinding upper beam and focuses the light on the street surface.Works best if you use a mirroring sticker on the inner side.Designed for ABS-like resin.It is adjusted to tight fit, theoretically no glueing needed.If you print it, don't forget to build in your resin's shrinkage. Now it is set for 2% shrinkage, you better make a trial print and adjust.