Inform visitors and send them in the right direction. Indoor changeable letter directories are available with a magnetic, plastic, or felt surface. Letters fit into place neatly on the black surface of each board.The felt and plastic and vinyl letter boards feature a grooved surface that accepts pin-style characters. Ridges on the magnetic surface secure the grooved molded magnetic letters.The anodized aluminum casing has full-length hinged doors with solid disc tumbler locks and shatterproof, clear acrylic doors. For indoor use. Magnetic