Adjustable Knob:There is an adjustable rotary knob on the center pole of the patio umbrella base to securely fasten φ 38 mm and 48 mm/1.5 inch and 1.9 inch patio umbrella poles to the umbrella stands. The patio umbrella stand can be better adjusted and adapted to umbrella poles of different diameters. Square Base, Stable and Beautiful: The 15-inch outdoor square market umbrella base is more stable and helps keep patio and market umbrellas firmly in place. The sun pattern adds charm and elegance to this product. Durable Material: This patio umbrella base crafted with high quality resin, waterproof, UV resistant, rust free and long-lasting,Withstand the test of time and can serve your outdoor umbrella for a long time Perfectly Suitable for Various Scenarios: With excellent stability, durability, weather resistance and stylish retro appearance, this umbrella Base is perfectly suitable for different scenarios such as garden, backyard, poolside, patio and so on. We recommend that you combine the patio umbrella base with a patio table Quality Service,Buy with Confidence: At FRUITEAM, each product undergoes strict quality inspection, to ensure that you receive are satisfied with the product, high-quality umbrella stand will make your life more convenient, your satisfaction is what we have been pursuing! FRUITEAM 24lb Outdoor Square Umbrella Base, 15" Patio Stand, Heavy-Duty Market Table Base (White)