BR Class 33/2 are a small sub class of the popular Class 33 and there were only 12 built to a narrower loading gauge than the majority of the class. Affectionately known as 'Slim JIm's' on account of their narrow bodies , they were generally confined to the South East until the early/mid 1980's, when they were increasingly found throughout the South of England, Wales and even North Wales occasionally. They were popular with enthusiasts as they were initially (1960's and 70's) more commonly used on freight traffic and rarely seen on passenger work., however as their freight work declined, they were more frequently to be found on passenger duties.

Withdrawn in the early to mid 1990's, there are 4 of the 'Slim Jim's' preserved.