This antibody recognizes a polymorphism variant of CD16 alpha antigen, which is a low affinity receptor for aggregated IgG (Fc gamma receptor III). The receptor exists in two distinct forms: a glycosyl phosphatidyl inositol (GPI) form (Fc gamma RIIIB), and an integral membrane protein (Fc gamma RIIIA). In humans, the transmembrane form is expressed on NK cells and macrophages whereas the GPI-linked form is expressed on granulocytes. This antibody binds both forms but binds poorly to NK cells from donors not carrying the polymorphism. The antibody can be used for detecting CD16 in flow cytometry, immunoprecipitation, western blot and blocks ligand binding.