BP Fluor 546 (Alexa Fluor 546 equivalent; AF546) is a water-soluble, pH-insensitive (from pH 4-10), orange-fluorescent dye with absorption and emission maxima at 554 and 570 nm, respectively. It can be used with the 488 nm and 532 nm laser lines. BP Fluor 546 conjugates to a variety of antibodies, peptides, proteins, tracers, and amplification substrates which are often used for generating stable signals in imaging and flow cytometry.