Goat anti-human IgM (u chain), F(ab)'2 fragment is a FITC conjugated secondary antibody which binds to human IgM (u chain), F(ab)'2 fragment in immunological assays. Fluorescein-5-isothiocyanate has Amax = 494 nm, Emax = 518 nm. Fluor to protein ratio is 3-7 moles FITC per mole antibody. Antibodies are affinity purified using solid phase human IgM.