After the KFNB had ordered the first five freight locomotives in the 0-4-2 wheel arrangement in England at the end of the 1830s, they began to manufacture their own freight locomotives at Wiener Neustadt in 1844. Based on the 4-2-0 type from Norris, the bogie was converted into a fixed frame part and the second leading axle was replaced with a coupled axle. The cylinders were still mounted in an inclined position next to the smokebox and still drove the rear axle. Because of the low-pitched boiler, the ashpan of the deep firebox reached just above the top of the rails.

The locomotives were given the names “Koloss” and “Elephant” and were delivered in 1844. In 1853 and 1865 they received new boilers with a larger heating surface. Although they were normally only known by their names, they were internally numbered 43 and 44. According to the new scheme from 1869, they were classified as series I and given the numbers 308 and 309. They were retired two years later.