Reflective stickers reflect light back toward their light source. Perfect for the back of your vehicle as the person's headlights reflect the light back toward them. For subliminal application put a reflective black (our favorite) on something like a dark window and it is harder to see during the day, but at night it is a beacon. Create your own speed trap with reflective blue which mimics the effect of a police car at night, an awesome way to slow cars down in an area abundant with speeding. These are made from a very high quality material and last 15+ years depending on the weathering it receives from sunlight, etc.