The image is a photograph of a white sign attached to a black metal railing. The sign is rectangular in shape and has Chinese text written on it. The text reads "0.4MPa" and "0 8MPa". Below the text, there is a diagram of a circuit board with various components such as resistors, capacitors, and transistors. The circuit board is labeled with the names of the components and their corresponding numbers. The background of the image shows a building and a tree.