The letter C of the test card indicates that one represents COVID-19 antigen test negative, while the letter CT of the test card indicates that two represents COVID-19 antigen test positive, and the test is dark, indicating COVID-19 antigen test positive.

Zhejiang Dongfang Gene Biological Products Co., Ltd. was established and put into production in 2008. Dongfang Company is a modern high-tech enterprise with pharmaceutical biotechnology as its pillar industry. It is an important base for R&D, production and sales of in vitro diagnostic reagents with gene diagnosis technology as the main body and new anticancer drugs with gene therapy as the main body in China.