China is not only the global manufacturing base for thousands of everyday household items, it is also the source of most of the world's torture instruments, from spiked clubs and electric stun batons to weighted leg cuffs.
China's manufacture and export of "intrinsically cruel, inhuman and degrading" law enforcement equipment has surged in the past decade, according to a report published on Tuesday by Amnesty International.
The number of Chinese companies producing such equipment, much of it banned in the EU and condemned by the UN, has more than quadrupled to 130 in the past decade, the report said.
Many of the worst items, including thumb cuffs and rigid restraint chairs known as "tiger benches" in Chinese, are exported to countries with poor human rights records in Africa and southeast Asia.
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"This trade – which causes immense suffering – is flourishing because the Chinese authorities have done nothing to stop companies supplying these sickening devices for export or to prevent policing equipment falling into the hands of known human rights abusers," said Patrick Wilcken, security trade and human rights researcher at Amnesty.
Torture by police and law enforcement officials in China itself is well-documented and many of the items singled out by Amnesty are used extensively in the country.
Although China's top authorities have vowed to stop the use of torture to extract confessions, the practice remains widespread.
In its report, Amnesty said China is the only country to manufacture spiked batons, which are "specifically designed as implements of torture".
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It identified seven companies that openly advertise these batons for export and said they have been used by police in Cambodia and exported to security forces in Nepal and Thailand.
Chinese-made electric shock batons, often used to torture detainees in China's notorious and recently abolished reform through labor detention camps, are sold to several countries in Africa, according to the report.
Many of the Chinese companies identified in the report are state-owned or have deep ties to the government or domestic security services.
Amnesty also criticized the UK for hosting arms fairs in London and other parts of the country where illegal Chinese equipment is advertised.
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The group has documented several cases where banned equipment such as electric shock stun guns, batons and leg cuffs has been on display at these events.
"The UK government has never prosecuted any company for illegally peddling torture equipment at UK arms fairs, despite numerous repeat offences dating back over a decade," said Oliver Sprague, Amnesty's arms program director.
"The UK's public rhetoric is that it has the strongest laws to ban this trade, but its actions so far have demonstrated the complete opposite. We want assurances that this is the end of the UK playing the dirty role of matchmaker between trader and torturer."