The words of Amos, who was among the herdsmen of Tekoa, which he saw concerning Israel in the days of Uzziah king of Judah, and in the days of Jeroboam the son of Joash king of Israel, two years before the earthquake.
"Uzziah ...  Jeroboam ..." See the introduction for a discussion of the dates of these monarchs.  The words "son of Joash" given in the identification of Jeroboam distinguish him as Jeroboam II.