A COVID-19 Rapid Diagnostic Test, a simple testing device similar to a pregnancy test.
They're a lateral flow test used to determine either COVID-19 antigens for a current infection or COVID-19 antibodies for having had a past infection. The antigen test features marks for C and T, where a single line on the C indicates negative for infection, while a line at both C and T indicates a positive for infection. The antibody test features the marks C, IgG, and IgM or C, G, and M. Having a line at the IgG or IgM mark indicates the presence of antibodies and having had a past infection.
