The Ephod for the High Priest: Worn Over the Robe
Source: TTT
Exodus 28:31
You are to make the robe of the ephod entirely of blue cloth,
Leviticus 8:7
He put the tunic on Aaron, tied the sash around him, clothed him with the robe, and put the ephod on him. He tied the woven band of the ephod around him and fastened it to him.