Material: HDPE and Steel, Product size: 20.0 "L X 20.0 "W X 13.16"H Adjustable knob: Tighten the adjustable knob on the steel pipe to ensure the best strength and stability regardless of the size of the umbrella pole. Controlling water spray: The umbrella stand can be filled with water at will according to your needs. Maximum water filling capacity: 48.50LBS Fit for Patio umbrella pole diametre of 1.5inch，1.89inch