It demonstrates the presence of metaxhromatic granules found in Corynebacterium diphtheriae.The granules stain purple -black against light green counterstained cytoplasm. It helps to distinguish Corynebacterium diphtheriae from most of the short nonpathogenic diphtheroids which lack granules. Contains: Albert's stain A solution (Product code 00823) -125 ml and Albert's stain B solution (Product code 00824) -125 ml