
Besides producing communications equipment and electronic wiring, Oki Electric Works specialized in construction and installation work for telephone lines, electric bells, and lightening rods for government offices in Tokyo.
When the company installed telephone lines to enable communication between the first and twelfth floors in the Ryounkaku ("cloud scraper"), the project received a lot of publicity. This twelve-story tower built in Asakusa and modeled on the Eiffel Tower, was, in the late Meiji period, a great symbol of the masses and their pleasures.

Business boomed so a new factory was built in the Kyobashi section of Tokyo, with a sales department, following two years later.
The creation of a telephone market by the Ministry of Communications led to expanded operations for OKI, turning it into Japan's top manufacturer of communications equipment.
The government introduced the First Telephone Expansion Plan and the following period witnessed a significant development in the early years for OKI. Orders to overseas manufacturers from the government increased, and domestic communications equipment manufacturers assumed the role as agents for imported products. OKI was in a natural position to take advantage of this and moved to expand the line of products it handled.