| Establishments primarily engaged in the preparation of poster displays and painted and electric spectacular displays on billboards, panels, bulletins, and frames, principally outdoors. Such establishments may construct, repair, and maintain display boards and may post advertisements. Special trade contractors primarily engaged in erecting display boards are classified in Construction, Major Group 17. Establishments primarily engaged in manufacturing electrical, mechanical, or plate signs and advertising displays are classified in Manufacturing, Industry 3993. |
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