What is the small light on a car called?

[MacSpencer]

Car small lights are actually position lights, also known as width marker lights. They are a type of warning light generally installed along the edges of a car's roof to indicate the vehicle's width. The function of car small lights is to alert other vehicles during dusk or nighttime driving, helping them judge relative positions and vehicle sizes when meeting or overtaking. Situations requiring the use of car small lights: 1. Driving in fog: With low visibility in foggy conditions, turning on position lights along with fog lights provides effective warning to help other vehicles identify yours; 2. Rainy weather: During poor visibility in rainy conditions, using small lights alone serves as a warning; 3. Evening driving: When roads are still clear at dusk but lack street lighting makes surrounding vehicles indistinct, activating small lights enhances visibility for safety.