E Tū union members have walked off the job five times this year, some fed up with working 60 hours a week on minimum wage at the Māngere factory.
Solo mother of four, Maria Latu, has been with the company for more than three years.
She works 12 hours on night shift for $16.50 an hour and says she's struggling to meet her family's basic needs.
"Standing 12 hours, $16.50 and we're only asking for 25 cents more and they're still not giving it.
"They're getting a lot in their pocket for our hard work on the floor. We're getting nothing. It's been almost over a year now we've been trying but still nothing has changed."
Another worker and mother of three, 'Ilisapesi Talanoa, says Sistema bosses are purposely ignoring their demands.
"Financially we are struggling to pay bills and to provide the necessities that we need for our families. They do see it, but they just turn their eyes."
Formerly owned by Kiwi founder Brendan Lindsay, the plastic-ware giant famous for its clip-it plastic containers was sold in 2016 to an American company for $660 million.
E Tū Union advocate Mat Danaher says Sistema products are sold in 91 countries worldwide and is succeeding on the backs of low-wage workers.
"The workers have had enough. They've put up with it for a long time... Their employer refuses to recognise the contribution they make to the success of this multi-million dollar business and has basically openly told them, 'If you don't like it you can go somewhere else, we're not prepared to raise the wages'."
Latu and Talanoa say on top of low wages, work conditions are also a problem they're seeking for Sistema to improve.
"People get blisters on their hands, sore backs, cuts," says Latu.
"The reason why we get blisters is because the product that comes off the conveyor belt is still hot and we need to clip them straight away otherwise it'll be overloaded... They don't provide us with gloves," says Talanoa.
"When it comes to winter it gets really cold... their comment was put more layers on before we put our vests on. And then come summer, it's really hot. If it wasn't for the union the fans wouldn't be up, we wouldn't get free beanies or vests or jerseys. If it wasn't for them we wouldn't get anything."
Since union members have raised concerns, Sistema has hired temporary workers to fill in roles during periods of industrial action.
But the Latu and Talanoa say even the temporary workers cannot handle the job.
"Having five strikes now, it's taking its toll on the floor. We can see the stress in the managers and the supervisors," says Talanoa.
"Even temps ask to go to the toilet and they go and never come back. They said it's too much and they can't handle it."
Latu says Sistema is hiring up to 75 temps a night to cover workers calling in sick and who aren't willing to work long hours for very little.
"They're able to pay them, but they're not able to give us the money they're paying for temps. They still don't value us. We're the ones putting the money in their pockets and they don't see it."
Danaher says workers will continue to take action until they get a fair deal.
"For low paid workers to take a hit by going out on strike, it's difficult for them it's not easy at all. Yet they're prepared to do it and they're prepared to keep fighting."
Latu and Talanoa say it'll mean the world to get a fair deal before Christmas.
"If people see the kind of work that we do on the floor, they'll know that we deserve a lot than what we're getting now," says Latu.
"There are families with only one parent working and it'll mean the world to them to get this just before Christmas," says Talanoa.
A media spokesperson from Sistema says there's nothing further to say at this point.