Abstract: The reflector attaches to the rim of a wheeled vehicle and revolves about the center of the wheel, thus following an eccentric path when the vehicle travels in a straight path. The reflector has one surface which is substantially parallel to the plane of the wheel and another surface which extends transversely of that plane. In this manner, the driver of the vehicle may easily see the reflections and a stationary observer may also be aware of the reflector. While the wheel is rotating, the path of the reflector becomes obvious and in cases of wheels which have become locked due to defective brakes, or the like, the reflector will remain stationary and follow a linear path along the highway, thus giving an indication that the brake is defective.