Huck Norris MegaNorris Hamburger Protective Rim Insert – Tubeless 26 / 27.5 / 29″ 60mm Fits 33-40 mm Single. Two hard compound layers with one soft between them. The beefiest of all MegaNorris models the Hamburger is aimed for those riding downhill or racing enduro an the highest level. While the MegaNorris Hamburger might weigh more than others the performance is well worth the weight.