(A) Cross-sections through the F1 regions of the different maps show that states 1, 2, and 3 are related by ∼120° rotations of the γ subunit within the α3β3 hexamer (blue arrows). (B) Surface rendering of a map (State 1a) shows the bent FO region with a tubular feature that extends from the rotor-distal portion to the c8-ring (orange arrow). (C) Cross-sections through the FO region show α-helices from the a, b and A6L subunits (green arrows), a low density region in the rotor-distal portion (white arrow), the tubular extension from the rotor-distal portion to the rotor (orange arrows), and the c-ring (purple arrows). (D) Averaging the FO regions from the seven different maps shows all of the features mentioned above with an improved signal-to-noise ratio for some features. Scale bars, 25 Å.