CPT 4200 Series Typewriter

CPT was founded by Dean Scheff in 1971, and the original product was a cassette tape base memory add-on for IBM Selectric typewriters (The name CPT originally meant Cassette Power Typing).

CPT grew into quite a large corporation, producing more dedicated word processors and even CP/M disks for the later models before ceasing to exist in the early 1990s. In 1975 Burroughs apparently agreed to distribute CPT Word Processors.