The VH41800 rail is a 6ft section ideal for hanging heavy weight art specimens. Rails attach the wall; rail clips can be moved along the rail, allowing you to position frames exactly where desired. For wall installations, fasten the VH4 rail to a vertical surface with hardware spaced 12″ to 18″ appart. The VH4 rail is designed to be installed before completing wall finishes (drywall, plaster, etc.) and painting.