The Treasure Garden Classic Anthracite Umbrella Base is made of durable cast iron and comes with a dual-purpose stem for versatility. The stem fits umbrella poles up to 1.5", which is ideal for free standing shade or to be positioned under the table. The full stem can be used in free-standing applications, while the reduced stem is ideal for under-the-table use. If the 50 lb. weight isn't enough for your purposes, the 30 lb. add-on weight can be added to this base, which is sold separately.