These belts fit most Nakajima made electric typewriters that were sold under a variety of brands like Royal, Olympia, Swintec, Sears and more, if your model has the motor and drive hub assembly as pictured, these will work. These belts give quite and reliable performance and brings new life to these typewriters that most of the time have bad belts.

Sample models are:

Olympia Japanese made Report, Reporter and CE-12

Sears Scholar, Graduate, SR3000

Swintec 3300C

Royal Academy, Office Master, Aristocrat 

Most likely fits many more.