There’s a reason people in the U.S. can get children’s toys for so cheap.
About 75% of the world’s toys come from China, where migrant workers are paid an average salary of $US240 a month.
Extreme poverty in China’s rural areas drives many people from the countryside into the cities to look for these types of jobs.
Wolf visited five toy factories in mainland China and has given us permission to share his photos with you here.
Alaina McConnell and Kim Bhasin contributed to this report.
Every day, the workers have to arrive 15 minutes before the regular work shift begins for a work assembly.
Their living conditions are prison-like. Up to six people share small, cramped dormitories and up to 50 people share one bathroom.
Rather than learning skills related to their respective disciplines, the students work as frontline production workers.
Even during the 30-minute lunch period, workers must return to the shop floor early to resume production or to attend another meeting. They're not paid for the time spent in these meetings or assemblies.
Female workers rarely get maternity leave, and with extreme hours and no childcare facilities they often cannot take care of their kids.
Toy production involves close contact with chemicals that are incredibly harmful to the workers' health.
This results in alarmingly high levels of occupational disease and work-related injuries. In 2009, about one million people were injured at work and about 20,000 suffered from diseases due to their occupation.
Many factory workers are not even required to wear safety equipment, including those who spend extensive amounts of time spray painting toys.
Workers can usually jump from job to job fairly easily, but they typically don't receive a substantial pay increase.
How did it get like this? Before opening up its economy in the late '70s, the Chinese government issued tight control between rural and urban areas, which encouraged people to migrate to cities illegally.
According to War On Want, 'These controls were part of the permit (hukou) system, in which welfare entitlements such as pensions, housing, health, and education were tied to a person's place of birth.'
But as China moved toward a market economy, cheap rural labour became integral to the country's growth.
The limitations on migration were reduced and about 85 per cent of China's rural poor flocked to the cities in search of employment.
Migrant workers became unable to access state benefits or protection, despite Chinese laws promising 'equal rights' for all.
They endure poor working conditions such as excessive and forced overtime, yet they don't even have basic social security benefits or employment contracts.
The workers' lack of awareness of their own rights and the Chinese government's unwillingness to address the abuse only perpetuate the system of inequality.
Despite the terrible working conditions, workers are optimistic that they will be able to gain new skills and create a better life.
Michael Wolf, the photographer of this series, has a display made out of 16,000 toys purchased second-hand from flea markets and stores across California. Each toy has a face and was 'made in China.'
Business Insider Emails & Alerts
Site highlights each day to your inbox.