This is a brand new thumb screw for the ribbon to work on Olivetti and Underwood typewriters. Without it, the ribbon movement will not work properly, the spool nut is installed on top of the ribbon to hold it down and rotate it.
This screw is made of high-quality, stainless steel. It is essential for a properly working Olivetti/Underwood typewriter.
It will fit all of the following models:
Olivetti:
Olivetti Lettera 22 * Olivetti Lettera 31 * Olivetti Lettera 32 Olivetti Lettera 33 * Olivetti Studio 42 * Olivetti Studio 44 * Olivetti Studio 45 * Olivetti DORA * Olivetti Lettera DL
Olivetti Underwood:
Olivetti Underwood 21 * Olivetti Underwood 310 * Olivetti Underwood 315 Olivetti Underwood 319 * Olivetti Underwood 320 * Olivetti Underwood DORA