Three-dimensional volume rendering of He-rich ejecta near the reverse shock, with opacity scaled to reflect density variations, shown from different viewing angles. The visualization is based on model B18.3 at t = 36 years after the SN (corresponding to February 2023). The color bar in the upper right indicates the He density. The blue circle indicates the nominal position of the equatorial ring. Earth’s vantage point corresponds to the negative y-axis.