Unilamellar vesicles were prepared in a manner identical to that for SAXS experiments. Cryo-TEM was carried out at the Stanford Cryo-Electron Microscopy Center (cEMc). 3-5 μL of an SUV dispersion was applied to a Quantifoil holey carbon grid (Quantifoil Micro Tools GmbH) that was previously glow discharged, blotted for 1-2 seconds, and plunge-frozen in liquid ethane using a Vitrobot Mark IV System (Thermo Scientific). The frozen grids were imaged with an FEI Tecnai F20 electron microscope (FEI Company) equipped with a Gatan K2 Summit direct detection device (Gatan Inc) with a dose rate of 6-10 e -/px/s. A low pass filter of 0.1 and mean shrink of 4 were applied to the raw images for visualization only. The raw images were processed with RELION 3.0. Overlapping regions of the bilayers were picked with the manual picking tool, extracted, CTFcorrected, and 2D averaged. The 2D classes with good alignment were reclassified into a single 2D class. The electron scattering profile of the bilayer was calculated by taking a line profile of the 2D classes in FIJI (ImageJ).