CatEye TL-LD710-R Rapid X2

The 2015 Cateye TL-LD710-R Rapid X2 is a taillight. Twice as bright as the X for exceptional visibility, with all its features, including mode memory, auto-switching to low-power mode for up to an hour of additional light, and six modes for any hour riding. The transparent orange housing increases side visibility. Mounting options are many; the included band mount works anywhere from seatpost to fork leg.
A very good taillight.