Wheels for carpet, free-running. What to know about casters for office chairs. Carpet wheels free-running Are made of very hard plastic so they glide easily over the carpet, but especially on a wooden floor, they make dents and eventually the floor breaks down. Furthermore, carpet casters are free-running, meaning that when you use carpet casters on a hard surface, your chair will keep going “endlessly,” it will shoot across the room. Wheels for hard floors, half braked The rim of these wheels is made of softer material, therefore they do not scratch. Often an office chair is always in the same place, i.e., it is constantly driven over the same spot. Particularly with softer woods, such as spruce, for example, wear spots can still occur. Then you’d better use a mat in addition to these wheels. These wheels are half-braked, which means that when you are not sitting on the chair, the wheels run a little heavier, which keeps the chair from sliding across the room. When you sit on the chair, this inhibition is removed and the chair rides smoothly. You can use wheels for hard floors on carpet as well, it just rides a little heavy.