Flexible design- This deck umbrella mount is suitable for umbrella poles with different diameters of 1.5-2 inches,and can be firmly fixed on square balcony railings and benches and other wooden railings. Durable material- Umbrella holder outdoor made of heavy-duty steel,this patio umbrella stand is designed with a smooth black coating to prevent rust and ensure longevity,and umbrella base sturdy all-welded seams prevent breakage very sturdy. Stability- Using 2 patio umbrella holder at the same time increases the stability of the umbrella. Securely attach the deck umbrella stand to square balcony railings,benches,fences,backboards,boats,poles,log cabins,tree stumps and more. Easy to install- Umbrella clamp can be installed quickly and easily and comes with eight screws to securely fasten the deck umbrella stand to decks and railings. The patio umbrella base heavy duty installation can be completed in minutes Save space- With the help of the accessories on the balcony railing,you can leave more space for use. Designed to provide instant and convenient shade. Great for barbecues,outdoor work and other recreational activities..