Roller barrier is a safety system used on roads to absorb and redirect the impact energy of vehicles that collide with it. The system typically consists of rotating cylinders made of durable materials like plastic or rubber mounted on a steel frame.

These cylinders roll upon impact, helping to reduce the force transferred to the vehicle and keeping it on the road, thus preventing more severe accidents. This design is particularly effective on curves or dangerous sections of roads where vehicles are more likely to lose control.