The system is very convenient. I installed it and it works pretty good. Installation is a little tricky because you have to find a way to have a minimum space between the lamp and magnets, which does not happen in one shot. Moreover, product picture is misleading because it shows four sets of magnets so that the box contains only one. It's really very little: one magnet at each wheel does not generate, in my opinion, enough energy to have sufficient flash even at low speeds. You must buy at least 2 magnets and more.
