Signs can be attached to Blockader barriers for identification purposes, theft protection, or advertising. Here, a sign identifies this barrier as the property of the United States Supreme Counrt Police.  Note that the sign is attached at each of its four corners via the nuts and bolts through pre-drilled holes. The barriers are galvanized after the holes are drilled, leaving no steel exposed.  With barrires featuring pre-drilled holes for signage, a message can be easily changed when needed.