39-703DC BR Mk2F BSO Brake Second Open Virgin Trains (Original) 9522 - DCC FittedBritish Rail's second generation of Standard Coach design is known as the Mark 2. Design and construction followed on from the universal and ubiquitous Mk1 family of coaching stock, with the prototype example built in 1963. Series production continued until 1975 at Derby Carriage Works. They were of steel construction, and of a more monocoque design than the Mk1, which added to their safety and integrity in event of collision or mishap. As passenger