Tune's Gum Gum is one of the lightest aftermarket expanders available. Other manufacturer's expander plugs are overbuilt and may damage some carbon steerers if overtightened. The Gum Gum's design is minimal; effectively strong, but not overly so. No metal contacts the inner wall of the fork when this expander is used, preventing any possibility of damage. This design features silicone rubber sandwiched between two 7075 T6 aluminum plates. As the top cap bolt is tightened, pressure on the silicone piece pushes it outward, and friction holds the assembly in place.
Please measure the inner diameter of your fork's steerer tube before ordering to ensure compatibility.