Nanjing Julong, listed on the ChiNext stock market, received an inquiry letter from the Shenzhen Stock Exchange on Aug. 10, after it recently said it had supplied , , , and triggering a sharp rise in its stock price.

A document issued by the Shenzhen Stock Exchange on Tuesday asked the company to detail by Friday its supplier certifications, supplies, business revenue and share, current production capacity and orders in hand with BYD, , Nio, Xpeng, Li Auto, and Evergrande Auto.

The document asked Nanjing Julong to explain the types of products currently available for energy storage, the progress of product development, and capital investment.

Nanjing Julong replied to investors on August 9, saying that the company had been certified as a supplier by new energy vehicle manufacturers such as BYD, Geely, Nio, Xpeng, Li Auto and Evergrande Auto.

The company's shares gained by the 20 percent daily limit on Monday and at one point rose nearly 17 percent more on Tuesday, before now narrowing to about 7 percent as of market close. The company has gained more than 40 percent in the last 10 days.

Nanjing Julong previously said it is engaged in the research, development, production, and sales of new polymer materials and their composite materials.

The company achieved revenue of RMB 1.14 billion ($176 million) in 2020, up 19.45 percent year-over-year, while net profit was RMB 61.17 million, up 108.96 percent year-over-year.

In the first quarter of this year, the company's revenue was RMB 376 million, up 150.83 percent year-over-year; net profit was RMB 151 million, up 196.34 percent year-over-year.

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