...
Do not rub them, as this will reduce their retro-reflectivity by removing glass beads the coating from the surface.
As far as possible, avoid handling the markers with bare hands to reduce contamination from skin oils.
...
Do not rub them, as this will reduce their retro-reflectivity by removing glass beads the coating from the surface.
As far as possible, avoid handling the markers with bare hands to reduce contamination from skin oils.