The class IV f locomotives of the Grand Duchy of Baden State Railway (German: Großherzoglich Badische Staatseisenbahnen, G.Bad.St.E.)

These were the first Pacific locomotives in Germany and the second in Europe after the Paris-Orléans Railway 4500-series that had appeared a few months earlier.

The 4-6-2 wheel arrangement and the bar frame were adopted from America, while four-cylinder compound engines of the Borries type and the sleek design are of German origin Because the locomotives were to be used both on the flat Rhine Valley route and in the mountains on the Odenwald and Black Forest railways, they had a driving wheel diameter of only 1,800 mm (5 ft 10+7⁄8 in).

The small driving wheel diameter for express steam locomotives led to comparatively high revolutions per minute.

With the successor series IV h, a drive wheel diameter of 2,100 mm (6 ft 10+5⁄8 in) was consequently chosen.

The boiler was pitched relatively highly with a height of 2,820 mm (9 ft 3 in) on the centre line In order to accommodate a large grate area, it was moved behind the coupled axles.