Riot control fence you also could call it crowd control barrier or mojo barrier. Maybe you are not familiar enough to this product, after all hey are frequently visible at sporting events, parades, political rallies, demonstrations, and outdoor festivals. Crowd control barricades are most commonly made of steel, although lighter-weight plastic variations are sometimes used. Barriers are most effective when they interlock, being attached to each other in a line via hooks at the side of each barricade. When barricades are interlocked, security personnel can create impenetrable lines, because such lines of barriers cannot easily be toppled over.