Clone C66/261 is a mouse monoclonal antibody specific to the human gene, CEACAM5, or Carcinoembryonic antigen related cell adhesion molecule 5. Another name for the gene is CEA. This antibody clone has been reported to also recognize the primate ortholog of the target gene. Indicated applications for antibody clone C66/261 include Western blot, immunohistochemistry, flow cytometry, immunofluorescence, ELISA, immunocytochemistry, and immunoprecipitation.