I’m white in the front and red in the back. What am I usually on the sides?*
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*The wording to this puzzle was refined by Will Shortz
This is a vehicle’s lightning system: the lamps facing frontward emit white light, the lamps facing rearward – red light, and the lamps facing sideward and all turn signals emit amber light.
Some vehicles in the USA can have rear turn signals red, while front – always amber ones. In majority of other countries both front and rear turn signals are of the amber light. Because of some regional differences the keyword “usually” has been used in the wording.