The Oliver Typewriter Company Twin-Spool OTTE-1643 Typewriter Ribbon for Manual Typewriters is compatible with many portable and standard vintage typewriters. The integrated reversing grommet provides a seamless typing experience. Versatile 2-color ribbon allows you to switch between ink colors. Typewriter ribbon is 1/2" on a 2" spool with 5-mm central aperture. Compatible with most Royal, Olympia, Smith Corona, Remington, Brother and more portable and standard vintage typewriters. Reversing grommet ensures a seamless typing experience. 2-color ribbon allows you to switch between red and black ink.