Why are billboards called anti-aircraft guns?

A billboard is called anti-aircraft gun because its structure has a thick steel tube column extending into the sky, which is shaped like an anti-aircraft gun.

1. Anti-aircraft guns are a kind of outdoor billboards. It mainly refers to setting up tall and eye-catching billboards beside major sections of highways, including expressways, urban highways and overpasses.

2. Common antiaircraft guns have two sides and three sides; There are a few four-sided anti-aircraft guns.

3. The size of the signboard is generally 3 to 1. The width of the signboard is 6 meters, the length is 18 meters, the height is 18 meters, the length is 7 meters, the height is 21 meters, and the length is 8 meters, the height is 24 meters. Adjust the height of the column according to the height of the road.

4. Anti-aircraft gun billboards are generally made of steel frame angle iron, but now there are a few grid structures. Install a rectangular or triangular card face on an upright post, and seal the card face with galvanized iron sheet or colored steel plate.

5. Make figures or words on the board for many people to see, so as to achieve the advertising effect.