The car bodies are unpainted with blue and white stripes representing the Genkai Sea.

[3] The longitudinal seats are covered with a red moquette and some parts of the saloons feature woodgrain panelling.

The 1000 series entered service on the Fukuoka City Subway coinciding with its opening on 26 July 1981.

Driver-only operation commenced on 20 January 1984, using automatic train control (ATC).

The cabs are equipped with a master controller, brake handle, and automatic train stop (ATS) system for manual operation.