HIV-1/2 RST is a chromatographic immunoassay (CIA) for the detection of antibodies to HIV-1/2 in human serum/plasma. HIV-1/2 specific antigens are precoated onto membrane as a capture reagent on the test region. During the test, specimen is allowed to react with the colloidal gold particles, which have been labeled with HIV-1/2 specific antigens. Antibodies to HIV-1/2, if present, a red colored band will develop on the membrane in proportion to the amount of HIV-1/2 antibodies present in the specimen. Absence of this red colored band in the test region suggests a negative result. To serve as a procedural control, red colored band in the control region will always appear regardless the presence of antibodies to HIV-1/2.