A close image of an IBM Selectric (light italic) typewriter ball, with the black branding and lock above the grey metal ball which strikes the characters. At the bottom is a sawtooth-edged opening where the ball is inserted into the typewriter for use.
https://files.mastodon.social/media_attachments/files/112/955/169/001/957/726/original/a34e55ece10653dd.png