We release a novel and extremely high quality monoclonal antibody to c-FOS MCA-1B62. This antibody was screened specifically to work on formalin fixed floating sections and we document that it can used to identify activated neurons and other cells in cell culture, tissue sections and formalin fixed paraffin embedded IHC materials. We also show it is significantly more sensitive than our widely c_FOS reagent MCA-2H2 and comparable to our also widely used rabbit polyclonal RPCA-c-FOS.