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Offline devices were typically Friden Flexowriters that had been specially built to operate with the FIO-DEC character coding used by the PDP-1.

Like the console typewriter, these were built around a typing mechanism that was mechanically the same as an IBM Electric typewriter.

However, Flexowriters were highly reliable and often used for long unattended printing sessions.

Flexowriters had electromechanical paper tape punches and readers which operated synchronously with the typewriter mechanism.

Typing was performed about ten characters per second.

A typical PDP-1 operating procedure was to output text to punched paper tape using the PDP-1's " high speed " ( 60 character per second ) Teletype model BRPE punch, then to hand carry the tape to a Flexowriter for offline printing.