For [Customer Name] - FACOM Flowchart Ruler - Extremely Rare - Fujitsu Ltd. Issued Template

This item is from the 1980s when I worked as a systems engineer.
It could even be called an antique.
Nowadays, we have drawing software, but
back then, we used rulers like this to hand-draw flowcharts.
I am listing it because it is no longer needed.

FACOM was a trademark used by Fujitsu for its own computers.
It comes from Fujitsu Automatic COMputer (before the trademark change in 1967, it was Fuji).
The FACOM brand was used as the main computer brand name until May 1990, when it was changed to FUJITSU.
In the United States, it is pronounced Fay-com.

FACOM began with the relay-based computer FACOM 100, completed in October 1954 by Toshio Ikeda (an executive from 1970-1974, senior managing director posthumously) and Takuma Yamamoto (president from 1981-1990).

FACOM's numbering system: the 100 series were relay-based, the 200 and 210 series were parametron, and subsequent models were electronic (transistor, integrated circuit).
In the early days, there were rules such as the last two digits being 00 for prototypes (100 and 200), the tens digit indicating the sequence, and the units digit indicating the number of digits of the computer. There were also rules where the tens digit being 0 meant a parametron for scientific use, 1 meant a parametron for business use, 2 meant a large general-purpose transistor model, 3 meant a transistor model for scientific use, and 4 meant a transistor model for business use. However, these rules all applied before the 230 series.
In the early days, numbers from 300 onwards were also used for computers, but later they were assigned to peripheral devices, such as the FACOM 603 magnetic tape unit. (Researched from Wiki)