PLUS refers to the additional protection built into each of our Outdoor boards.
Each cabinet door is lined with weather seal and has dual locks.18"x24" 1-Door Lighted Enclsd Outdoor Letterboard,Hdr,Blk Felt/Bronze Vent holes and drain holes are in the bottom and sides of each cabinet, for airflow. Create important messages or announcements that need to be outdoors with our Outdoor Plus Enclosed Letter boards with Traditional aluminum frames. A drip edge is mounted on the face of the cabinet, so rain runs off the front of the cabinet.