In the Czech Republic, all motor vehicle drivers must have their dipped lights or day lights on! Even during daylight. You will save up to 1,500 CZK in fines
And be seen
Pedestrians must wear reflexive elements in reduced visibility in the Czech Republic.
This is necessary when you walk outside an urban area in low visibility (not only at night, but also in dark conditions, fog, etc.) on the roadside or on the edge of the road where there is no public lighting.
For your own safety, however, it is of course good to use reflective elements wherever a driver might not safely see a pedestrian.