Exodus 37:1-3

Now Bezalel made the ark of acacia wood; its length was two and a half cubits, and its width one and a half cubits, and its height one and a half cubits; and he overlaid it with pure gold inside and out, and made a gold molding for it all around. He cast four rings of gold for it on its four feet; even two rings on one side of it, and two rings on the other side of it.