Reflective material. Coloured scanning electron micrograph (SEM) of an ant on some reflective material. The material (magenta and orange) is designed to be retro-reflective", that is, reflect any light which falls on it straight back at its source. This sort of material is used on the clothing of people who have to work in dangerous situations in low light, typically on roads or railway tracks, where visibility is essential. Similar techniques are also used on road signs and cat's eyes. Magnification: x20 at 6x7cm size."