Recent advancements in the field of protein science, such as the cryo-Electron Microscopy (cryo-EM) technique, have helped investigate, with an unprecedented precision, the structure of several proteins, including ion channels. Knowledge of the structural changes involved in channel activity allows to provide a molecular interpretation of the channel basic properties, described in early electrophysiological experiments, sometimes even decades before. This allows to validate, or refute, interpretation and modelling of original results.