The electron intensity profile resulting from SPA in Figure combines features of the results seen in SAXS, cryo-ET and FFT analysis. The SPA profile in Figure has an inner peak-to-peak distance of 60 Å, which is very well comparable to cryo-ET results of 60 Å, and aligns with the hydrophobic core region (56 Å) in the SAXS profile (its borders are determined by the zero-point positions of the profiles). The SPA profile also potentially has two slight shoulders at approximately ± 60 Å, which aligns with the peaks at ± 55 Å, ± 70 Å and ± 70 Å seen in SAXS, FFT and cryo-ET profiles, respectively. The 4-Gaussian model used for thick 50 mol% PBd22-PEO14 membranes does not account for these two additional positive electron density contributions in this structural region, which is why this particular feature cannot be reproduced in the SAXS or the predicted scattering pattern from a FFT of cryo-ET images.