An 'inertia reel' seat belt is one which?

An inertia reel seat belt is a type of safety belt that automatically adjusts its length based on the passenger's movement and provides tension during sudden stops or impacts. It utilizes a spring-loaded mechanism that locks the belt in place when rapid acceleration or deceleration occurs, helping to prevent the occupant from being thrown forward. This design enhances safety by ensuring that the seat belt remains snug against the body during a collision. Inertia reel seat belts are commonly used in modern vehicles for both front and rear seats.