I have two fairly similar LED taillights. On the one lamp I turn glued with superglue two neodymium magnets and lead them in the car with me, as a warning light for emergencies. That I, as once happened in a night Wildunfall, within fewest hours doing empty the car battery with the hazard warning lights of the car, can not happen to me with such a lamp. Here the seven flashing modes will eventually make sense then maybe.
For quality: the lamp is working, the power switch works reliably first (with 8 light modes!). It is fitted with a tight-looking rubber cap's housing. The brackets and the battery cover are stiff. The water resistance for years of use I can not judge, but I'm also not worry about it.