Few people have heard of Huangyan, a booming industrial district of Taizhou, a city in eastern China’s Zhejiang province. Yet without it, many cars would likely be heavier, more expensive and less energy efficient, while everyday household goods would probably cost more.

The town specialises in plastic components and moulding equipment – unassuming products that rarely make the news, but sit at the heart of modern manufacturing. For years, Huangyan’s producers have dominated this supply chain, leaving households and multinationals reliant on them.

In a world awash with plastic, the district’s importance is hard to overstate. Car interior trim, remote controls, keyboards, cosmetic packaging and many other goods are made with the versatile material. Many can be traced back to Huangyan’s factories, where resin pellets are shaped into a seemingly endless array of products.

“Without the factories here and the hidden champions of Chinese manufacturing more broadly, the world and many products that we’ve taken for granted, including Tesla cars, would be different,” said Huang Yue, secretary of the Huangyan Mould Industrial Association.

Long overlooked, the district’s manufacturers offer a snapshot of the depth and reach of Chinese industry – and, in the case of something as ubiquitous as plastic, how global consumers and companies have come to rely on the world’s second-largest economy.

But that dependence is mutual. Huangyan’s use of cutting-edge foreign equipment and technology reveals how deeply intertwined domestic and foreign players have become – and why talk of decoupling runs counter to realities on the ground.

Tesla’s hidden supply chain

The district’s indispensable role is especially visible in the automobile sector, one of the largest end markets for plastic moulds – identical, precise and complex parts that can be mass-produced at low cost.

Huangyan has built one of the world’s most comprehensive industrial chains for plastic injection moulding. Design, materials, precision machining and trial moulding are all clustered in a single ecosystem – invisible to consumers, yet central to China’s manufacturing prowess.