AAT Bioquest's mFluor™ dyes are developed for flow cytometry-focused applications. These dyes have large Stokes Shifts, and can be well excited by the laser lines of flow cytometers (e.g., 405 nm, 488 nm and 633 nm). mFluor™ Violet 540 dyes have fluorescence excitation and emission maxima of ~405 nm and ~540 nm respectively. These spectral characteristics make them an excellent replacement for Pacific Orange™ labeling dye. mFluor™ Violet 540 SE is reasonably stable and shows good reactivity and selectivity with protein amino groups. This kit has all the essential components to perform two separate labeling reactions with no purification needed. Each of the two vials of mFluor™ Violet 540 SE provided in the kit is optimized for labeling ~50 µg antibody. mFluor™ Violet 540 SE antibody labeling kit provides a convenient method to label small amounts of monoclonal, polyclonal antibodies or other proteins (>10 kDa) with the Violet Laser-excitable mFluor™ Violet 540 SE.