[BeauBo]

They use the term bollards for this type of barrier (Series of steel posts, that you can see through), even if it is thirty feet high.

They are often filled with concrete, and very difficult to attack with sledgehammers, chisels, saws or torches. They stand up much better than other barriers that have been tried - they will stop a truck. Border Patrol places a high value on being able to see what is on the other side.

[Davy Crocket]

They are also easy to climb. Didn’t you see the videos of those Hondurans sitting on top of the fence.. Solid reinforced Concrete with a Barrier at the top!!