Anti-Mouse IgG kappa, AlpSdAbs VHH(iFluor647) is designed for detecting mouse IgG kappa chain specifically, and Anti-Mouse IgG kappa, AlpSdAbs VHH(iFluor647) is useful for super-resolution microscopy. Anti-Mouse IgG kappa, AlpSdAbs VHH(iFluor647) is based on recombinant single domain antibody to mouse IgG kappa chain coupled to iFluor647. Based on immunoelectrophoresis and/or ELISA, Anti-Mouse IgG kappa, AlpSdAbs VHH(iFluor647) reacts with the mouse IgG kappa chain selectively, no reactivity with the mouse IgG lambda chain or heavy chain of mouse IgG.