A graduated release device which includes a valve, for example a check valve, connecting a control valve port and a brake cylinder port which prevents flow from the brake cylinder port to the control valve port. A graduating section controls the valve to produce graduated release of the brake cylinder in response to pressure on the brake cylinder port, brake pipe port and graduating volume port. An automatic mode section controls the valve to produce direct release of the brake cylinder in response to less than a predetermined value of pressure on the supply line port. If it is a two pipe system which includes graduated release, an appropriate pressure will appear on the supply line port and therefore allow the valve to be controlled by the graduating section. If less than a predetermined pressure is on the supply line port indicating that it is a single pipe system, the mode selecting section maintains the valve open such that it operates as a direct release valve between the control valve port and the brake cylinder port.

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