What is in the center on the back of the US 1 dollar bill?

The center of the back of the US $1 bill features the Great Seal of the United States. The front of the seal depicts an eagle holding an olive branch and arrows in its talons, symbolizing peace and war. Above the eagle's head is a constellation of 13 stars representing the original 13 colonies. The reverse side of the seal features an unfinished pyramid with the Eye of Providence above it, symbolizing strength and the watchful eye of a higher power.