Components: Human PF4 Antibody-coated ELISA Plate (Item A); Lyophilized Human PF4 Protein Standard (Item C); Biotinylated Human PF4 Detection Antibody (Item F); ELISA 5X Assay/Sample Diluent Buffer B (Item E1); ELISA 1X Assay/Sample Diluent Buffer C (Item L); HRP-Streptavidin (Item G); ELISA Stop Solution (Item I); ELISA Colorimetric TMB Reagent (HRP Substrate, Item H); 20X Wash Buffer (Item B)