On either side of an MX5 NB (1998 - 2000), the doors are an important part of the interior. This is where operation, comfort and finish come together in one structure that is used intensively on a daily basis. Door panels, handles, window controls and various trim parts largely determine how solid the interior feels while driving. Behind these visible parts are cables, guides and mechanical components that are in constant motion. For example, the doors work closely with the electrical systems responsible for operating the side windows, so proper operation of both systems is immediately noticeable in everyday use.