€¢ Triple arms with dual final support brackets €¢ Fits on any sized deck or fence railing from 1 inch To 4 inch Wide; not tools required €¢ Works on chain link; wrought iron; composite; and standard wooden rails €¢ Planter arms are adjustable and lower stabilizing Arm keeps planter perfectly level; regardless of fit €¢ Water reservoir holds 6 cups of water with auto-overflow; hidden tray separates plants from reservoir; with slits to allow only the roots to reach the water reservoir below; avoiding root rot >> Beautify your decks; fences; railings; & Sign posts with these ingenious adjustable railing planters. Lock the support arm to the desired width; hang & you are done! No tools; Mounting hardware; or drilling required. Ideal for wood or metal railings. Hidden lower bracket keeps the planter level. 3/4 inch Reservoir holds excess water. Includes soil tray."