This design follows the Helmholtz resonator approach: a hollow chamber with specific "necks" (ports) that dissipate tire cavity noise. It is designed as a curved segment that fits into the drop-center well of a 20" rim, using a flared base to wedge into the rim's geometry so centrifugal force keeps it seated. Design Approach Curvature: The segment is arched to match the internal diameter of a 20" wheel's center well. Chamber: A hollow internal volume with internal ribs for structural integrity. Retention: Flared "wings" on the base to clip into the rim channel. Tuning: Parametric neck diameter and chamber height to adjust the frequency response. Modular Assembly: You can print several of these segments to cover the circumference of the wheel. Printability: It is best printed on its side (profile face down) to avoid needing excessive supports for the hollow chamber, or with minimal supports for the ports. Printing Recommendation: Material: Must use ASA or Nylon.