Hong Kong and Macao brands' ongoing success during the Greater Bay Area Online Shopping Festival is an indication of how the two special administrative regions can prosper through integration and the nation's dual-circulation vision.

The dual-circulation development paradigm emphasizes that the domestic market is the mainstay of the economy, while the domestic and overseas markets reinforce each other.

The festival, which runs from Sept 2 to 22, features 298,000 brands from various regions and offers more than 13 million products on online shopping platforms. It was jointly organized by the Ministry of Commerce, the Guangdong provincial government and the central government's liaison offices in the Hong Kong and Macao SARs to boost the economy of the Greater Bay Area and promote the development of integration in the region.

In the first two weeks of the festival, 41,000 Hong Kong and Macao retailers generated close to 3.4 billion yuan ($530 million) in sales. Meanwhile, the amount of products shipped from Guangdong to Hong Kong and Macao grew 12 percent compared with the same period last year, with the turnover worth 270 million yuan.

Wong Wai-hung, standing committee member of the Chinese Manufacturers' Association of Hong Kong, said the development plan for the Greater Bay Area was the entry point for the Hong Kong SAR to integrate into the country's dual-circulation strategy.

He hoped that the festival would be a thought-provoking event that motivates more Hong Kong companies to make inroads into the Greater Bay Area.

Among the festival's success stories is Tao Heung, a food retailer and catering company established in 1991 in Hong Kong. Since it started an online store on Tmall, its sales skyrocketed by 300 percent in just six months.

For the upcoming Mid-Autumn Festival, it is selling mooncakes packaged in a lantern-shaped box, which have become a hit during the shopping festival. They were snapped up in an instant during a livestream promotion by Li Jiaqi, one of the biggest influencers in China's e-commerce industry.

Hong Kong's Imperial Patisserie has earned a reputation for high-end mooncakes by using premium ingredients, secret recipes and catering to health-conscious consumers.

Its signature treats sold rapidly during the online festival. "The shopping festival is not simply about selling, but more about putting our homegrown brands in the limelight. Under the lingering pandemic, the festival presents us with a much-needed stage to showcase our glamour," founder Martin Yim said.

Merchants in Guangdong also took advantage of the festival to make forays into Hong Kong and Macao markets.

Guangzhou Xiangxue Asia Beverage is a traditional brand and has gained popularity in South China because of the flavors of its carbonated drinks. As Hong Kong residents share similar tastes with people in Guangdong, they are also fond of such drinks. But the company has yet to explore the Hong Kong market.

"A Macao businessman approached us last year for cooperation, but the plan had to be shelved due to the coronavirus," said He Wenfeng, the company's chief executive. "We'd like to take the opportunity of the festival and tap more markets."

The company also launched a limited-edition beverage for the shopping festival. "Through the convenient logistics of Tmall, we hope more Hong Kong consumers can know about and try our special drinks," he added.

Tao Tao Ju, a catering brand founded in 1880, was pleased to see its sales of mooncakes on Tmall increase fivefold over the first two weeks of the festival, compared with the same period last year. It said it would double its promotions in Hong Kong and Macao markets.