Large cement slab - we had it as a table top on top of a tree stump, but could also be used for part of a greenhouse foundation or patio with other cement pavers. VERY heavy. Approx. 46 inches x 33 inches. Circle protrusion on bottom diameter is 28 inches. If the ad is up, its available. If you are interested, please message with the time you can pick up. Gorge Tillicum area.