Abba Patio Cantilever Offset Umbrella Base Plate Set, Black, Pack of 4 Designed for cross-base umbrellas; Made of durable plastic, long-lasting, weather-resistant and UV protection Each plate can be filled with 38 lb - 44 lb of wet sand. The whole base provides approximately 150 lb weight when filled with sand or 180 lb when filled with wet sand Sturdy 4-plate construction supports your offset patio umbrella stand perfectly Easy fill spout makes for convenient filling, cleaning, and storage Can be filled with sand so that plates provide additional weight required to improve umbrella stability in windy conditions