Around 40 workers at Crown Speciality Packaging in Bootle, Merseyside, struck on Friday of last week after the company dropped an agreed pay rise.
They are members of the Unite union. This was their second walkout, with a third planned for this Friday.
“Workers feel betrayed,” Unite rep Alan Bell told Socialist Worker.
“We went into agreement in good faith, it took a long time to work out, and then the company pulled out of it a week before it was going to come into force.
“We can’t just let that go.”
Crown makes metal tins, including for Cadbury’s chocolate. It had promised workers a 7 percent pay rise. But it now says only eight workers will get the money.