China's production of zippers is predicted to increase 20 per cent annually due to growing demand for bags, shoes, and sports merchandise, according to the China National Hardware Association (CNHA).

Data from CNHA showed zipper sales value in China totalling CNY25 billion last year, a figure contributing to nearly 50 per cent of the world's total.

Around 80 per cent of zippers made in China, the biggest producer of the items, are shipped abroad.