What are the dimensions and specifications of expressway height limit signs?

Standard dimensions of road traffic signs:

Don't close, someone is working! Size: 200* 160 and 80*65 color: white background, red slash, black forbidden symbol. Word: black word.

Don't close, the line is manned! Size: 200* 160 and 80*65 color: white background, red slash, black forbidden symbol. Word: black word.

No brake opening, size: 200* 160 and 80*65 color: white background, red diagonal line, black forbidden symbol. Word: black word.

Work here! Size: 250*250 and 80*80 Color: The base is green with white circles with diameters of 200mm and 65mm, and black characters are written in the white circles.

Extended data:

By setting cameras at road checkpoints, a monitoring and capturing system is established to monitor and capture vehicles passing through the monitoring area of road checkpoints in real time, and obtain information such as vehicle speed, traffic volume, vehicle license plate number, color, physical approximate size and driver characteristics.

Then the information is transmitted to the database of the public security traffic command center and the traffic control sub-center through the transmission network for data storage, query, comparison and other processing, effectively preventing illegal speeding.