Olympia SG1
From Typewriter Wiki
History & Basic Info
The Olympia SG1 is a highly regarded standard typewriter built by Olympia from 1953 to 1962, where they then changed production to the modernized Olympia SG-3. These typewriters are very large and bulky, but have established a reputation for being very good machines to write on. The quick-detach mechanism for the carriage allows a user to change carriages for different size papers, if you have those carriages. Nowadays it's really just used for convenient access to the machines' internals.
Common Problems
The grommets for the top cover often go bad and either dry out or crack so they are unusable. If you have an Ace Hardware around, the replacement grommet you want is item number 55056-F.