Bus 231 was a Bedford SB3 with body by Pressed Metal Corporation, Sydney.
It was purchased as a stock unit from Suttons Motors during the 1974 bus shortage and was registered on 29 July 1974. It entered service on 2 August 1974.
It was the only SB3 to operate in Canberra and was powered by a 4.93 litre ‘300’ petrol engine, which delivered 114 BHP.
Once leaving route service with ACTION in mid-August 1976, it was hired to ACT Police and then transferred to ACT Health with registration ZID-612. It later operated as a school bus in Jindabyne before returning to Canberra in 1990 to be used as a “night bus” for YMCA Canberra.