Members of the International Association of Machinists and Aerospace Workers at the plant in Joliet approved the contract Friday, the Chicago Tribune reported. The company more than tripled a ratification bonus to $3,100 before the vote.
Union members said the contract -- which freezes pay for those hired before 2005, doubles health-insurance premiums and reduces the benefits of seniority -- passed by a narrow margin. Many of those who voted against it were angry.
"I can't believe they did this," a tearful Vickey Pogliano said. "I'm shocked. I know there is a lot of people hurting but they didn't see the big picture."
About 780 employees struck May 1, although 100 had returned to work, union members said. The company said strikers will be brought back over about two weeks beginning Monday.
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