Abstract: In accordance with the present invention, a pressure indicator is mounted upon a railway car and is in communication with an opening into the pressure chamber of the car. The car may be, for example, a pressurized hopper car or a pressurized tank car. The indicator comprises a fixed assembly having a resilient member so engaging said fixed assembly that the resilient member may react against the fixed assembly. A movable assembly is provided, at least a portion of which is used to indicate the pressure in the chamber. A flexible diaphragm is provided in the indicator, preferably a rolling diaphragm, which is affixed to the fixed assembly and the movable assembly and enables the pressure applied to the indicator to be applied to the movable assembly against the bias of the resilient member and permit at least a portion of the movable assembly to indicate the pressure range in the tank. Preferably the indicating portion is color coded.