Comprehensive array inserts are marked on the top panel for arrayed applications. Delta 218B is ideal when used in arrays and is equally at home in a wide variety of fixed installation and touring applications. Rhino Rock™, our new texturised composite finish is used in all models. This new finish provides the great look of a painted finish with the durability of a carpet covered enclosure giving you the best of both worlds. The Delta 218B is constructed from plywood.