A chin strap is a component of a helmet that fastens under the chin and serves to secure the helmet firmly on the head. It prevents the helmet from accidentally falling off, for example, when bending forward, during an impact, a fall, or when working at heights and in windy environments. It is typically made of textile material and equipped with a buckle for easy fastening and length adjustment to ensure a precise fit. Some straps are designed to intentionally unfasten at a certain load, thereby preventing the risk of strangulation in case the helmet gets caught on something. Conversely, others, typically found on helmets for work at heights, have higher strength to keep the helmet on the head even during a strong impact.