Double-lock design: comes with 2 hand knob tightening screws with rubber tips to prevent scratching that hold the umbrella pole securely Durable material: the shell is made from weather-resistant plastic construction that filled with solid and sturdy cement lasting long service time Universal function: adjustable holder to fit 1.3"(32mm), 1.5" (38mm) and 1.9"(48mm) diameter poles, suits 7-11 feet market parasol umbrellas Multi-scenario use: applying for many leisure scenes like patio, deck, yard, garden, porch, balcony, swimming pool, lawn, outdoor cafe, restaurant, etc Efficient installation: easy to assemble, detailed manual instruction was provided, this classic product will make your outdoor spaces more attractive Helios&Hestia 26 lb Heavy Duty Round Plastic Built-in Cement Outdoor Umbrella Base, Concrete Weighted Stand for Patio Market Table Umbrella, Black