This kit is based on the principle of immunochromatographic testing and uses the capture method to detect the SARS-COV-2 Neutralizing Antibody in the sample. When the sample contains the SARS-COV-2 Neutralizing Antibody, it forms a complex with the gold-tagged protein (SARS-COV-2 recombinant RBD protein). The complex proceeds under the influence of chromatography and the T-line coated antibody combines with the Mouse anti-human IgG monoclonal antibody, which is a positive result. When the sample does not contain SARS-COV-2 Neutralizing Antibody, no complex can be formed on the T line and no red band will appear, which is a negative result. Regardless of whether SARS-COV-2 Neutralizing Antibody is present in the sample, the gold-tagged protein (SARS-COV-2 recombinant RBD protein) will bind with the coated antibody (goat anti-mouse IgG Antibody) in the C line. forms a complex and develops color (C line).