Description: It is a semi quantitative competition ELISA kit to detect the Anti-SARS-CoV-2 Neutralization Antibody in human serum or plasma. The micro test plate provided in this kit is pre-coated with recombinant human ACE2. During the reaction, the SARS-CoV-2 neutralization antibody in the standard & sample diluent pretreated samples or controls competes with a fixed amount of human ACE2 on the solid phase supporter for sites on the Horseradish peroxidase (HRP) conjugated recombinant SARS-CoV-2 RBD fragment (HRP-RBD). After 37℃incubation, the unbound HRP-RBD as well as any HRP-RBD bound to non-neutralization antibody will be captured on the plate and eventually form the ACE2-RBD-HRP complex, while the circulating neutralization antibodies HRP-RBD complexes remain in the supernatant and are removed during washing. Then a TMB substrate solution is added to each well. The enzyme-substrate reaction is terminated by the addition of stop solution and the color change is measured spectrophotometrically at a wavelength of 450 nm ± 2 nm.