This Butterfly Leaf Extension Table has two leaves concealed beneath the table top, each hinged and "folded" in half.  When an extension is needed, the table top slides open to expose the leaves, which open like the wings of a butterfly.  One or both leaves can be deployed as needed. The table pictured here is 42" x 84" when closed. Each leaf adds 16", so the table can extend to either 100" or to 116"