Fits slatwall or gridwall. Horizontal Universal Crystal Clear Acrylic Sign Holder. The horizontal acrylic sign holder measures 11"W x 7"H. Display your sign on slatwall or gridwall using this acrylic sign holder. The acrylic gridwall sign holder hooks on to any horizontal grid or slatgrid panel wire. The acrylic slatwall sign holder hooks onto the horizontal slatwall groove. Palay Display stocks a wide variety of slatwall acrylic sign holders and gridwall acrylic sign holders. In stock.