Cross section of the disk model suggested by our observations. The location and the height of the depicted rings is to scale, while the width of individual features is not. We use Ring 3 as an example to show the geometrical relation between the height and centre offset of individual rings assuming an axisymmetric disk. We note that the gaps in the disk are shown empty in this schematic view for simplicity, while in reality the gaps are likely not devoid of material. This figure was adapted from de Boer et al. (2016).