For decorative reasons, knurling can enhance the aesthetics of the wheel spacers by introducing an attractive pattern to the side surface. In addition to aesthetics, there are practical features. Knurling patterns can enlarge the side area so that it can contact more air, boost the heat dissipation effect, and also reduce internal stress. That means improving the performance, strength, and durability of the spacers. BONOSS aims to provide wheel spacers with more additional functions, safer, higher performance, more professional design, and better installing experience, that is why we insist on independent manufacturing and continuous optimization of the design.