What do the white squares and trapezoids mean on goods wagons?

Starting in the 1920's, the DRG (later the DB and DR) put indications on their freight rolling stock of what sort of brakes (air brakes not hand brakes) the vehicle had. These marks took the form of squares and trapezoids on the corners of the wagon. Usually these were white, but on some light coloured vehicles they are black, or at least have a bold black border.
In the 1970's they started going out of use, and most vehicles don't have them anymore.

It is worth noting that over the years, the German railways have used several different braking systems, and some of them are not compatible.


	This vehicle has no air brakes of it's own, but does have a 'blow-through' pipe. i.e. It can be coupled between 2 vehicles that DO have brakes, and the through-pipe on the unbraked vehicle couples the brakes of the other 2 vehicles together. Note that a vehicle with no air brakes of it's own can have handbrakes, and the associated brake cabin. You will find photographs of wagons with a brake cabin and brake shoes but that still has this symbol.

	This vehicle has a 'slow-working', freight-train brake system, and is suitable for interchange across Germany. The brake system on this wagon could be one of the following: Kunze-Knorr-Güterzugbremse Hildebrand-Knorr-Güterzugbremse Bozic-Güterzugbremse Drolshammer-Güterzugbremse Breda-Güterzugbremse

	This vehicle has a freight-train brake system that is not fully compliant with other systems and although it is suitable for interchange between differing German states, there are restrictions. Wagons built in Poland with an old form of Westinghouse brake fall into this category. Wagons of this type were taken out of general use towards the end of the 1950's, but were still to be found in departmental use after this date.

	This vehicle is only fitted with a passenger train brake system, and must NOT be connected to the brake pipe of a freight train.

	This vehicle has a G-P (Güterzug-Personenzug) brake change-over valve ('slow-working' for freight-trains, 'fast' for passenger), and is also suitable for interchange across Germany. Amongst others, this includes: Kunze-Knorr-Güterzug-Personenzugbremse

	This vehicle has a G-P (Güterzug-Personenzug) brake change-over valve ('slow-working' for freight-trains, 'fast' for passenger), but is NOT suitable for interchange between differing German states. Wagons of this type were taken out of general use towards the end of the 1950's, but were still to be found in departmental use after this date.