No, there's no reflective back up in the 3 manufactures road studs that i've just checked out. Only back-up is battery storage levels ...ie 240 hrs from from 3 hrs sunlight to fully charged (sunny day). which is pretty impressive. The manufactures are quoting around 10 consecutive working nights (dusk till dawn) on a full charge without any further charging.Don't get me wrong, seems quite a decent system, and a worthwhile addition to those areas of roads that have suffered from too many accidents.
It's just that when you introduce high technology to a system that had none previously, you also tend to introduce a degree of probable faults and failures.. I would imagine that the price of these units are pretty steep too, but what price do you put on a saved life??? A suck it and see situation!!!