Unlike wheel nuts, wheel bolts are single-piece screws that thread directly into the wheel hub itself. This design is most common on European vehicles. The bolt passes through the wheel rim and anchors into the hub. While they serve the same purpose as lug nuts, they can make changing a tire more difficult because there are no studs to hang the heavy wheel on while you align the holes. Like nuts, they must be torqued to specific manufacturer settings to prevent warping the brake rotors.