Single-flange level gauges typically include a float or diaphragm connected to a sensor that converts level changes into electrical signals and are suitable for level measurement in a variety of containers and open containers.
Double-flanged level gauge usually consists of two flanges, one mounted on the top of the container and the other mounted on the bottom of the container. The two flanges are connected by a capillary tube filled with liquid. When the liquid level changes, the height of the liquid in the capillary will also change, thus changing the pressure of the top flange.