A ready-made set of reagents for the detection of acid-fast mycobacteria (causative agents of tuberculosis and leprosy) in histological sections. Since the cell wall of mycobacteria contains a large amount of lipids and other wax-like  substances, when stained with carbolic fuchsin, they perceive color, and when discolored with strong acids, they retain their color, when the rest of the microflora is discolored, which is a differential test for mycobacteria.