Well MaterialOur umbrella holder is made of precision cutting aluminum, preventing corrosion and ensuring stability for long term use with a flat and smooth surface, beautiful and atmospheric appearance, which can be good integrated with the railing and the surrounding environment.Space-savingDeck mount umbrella holders provide more space on your deck or patio and are well for small decks. Easy to clean and store, suitable for home and commercial use,so deck mounted umbrella stand is an essential tool for life, and it can be used on any corner surface.Wide ApplicationOutdoor umbrella holder clamp stand's one-piece, six-hole locking is more stable suitable be instalon any pole, railing in your deck, patio, balcony, docks , it can provide protection from sun or rain and cover for those under the umbrella.Adjustment RangeThis patio umbrella stand is equipped with adjustable knob screws and can be adjusted according to the diameter of the umbrella post. Umbrella post diameter range: 1.3"-2". The umbrella stand has three hand-turn fastening knobs can securely attach the base to any railing ,not easy to shake, suitable for outdoor use in all weather conditions.Our ProductOur umbrella clamp mount bracket is quick to install and comes with 6 screws and three hand-turn fastening knobs.