Push/Pull DBSO Leaving Glasgow Queen Street is one of the original batch of ten Push/Pull Driving Brake Open Standards (DBSO) with the half cabs, these were converted from MK2 Brake Standard Open (BSO) coaches at BREL Derby works in 1979, for operating the Glasgow-Edinburgh InterCity push/pull service with dedicated 100mph class 47/7 locomotives., , 1st August 1984