R2A Agar is a non-selective and non-differential medium used for the enumeration heterotrophic organisms from potable water. It is a low nutrient medium that is incubated at a lower temperature for a longer duration, which stimulates the growth of stressed and chlorine-tolerant bacteria. When compared with Tryptone Glucose Yeast Extract Agar or Plate Count Agar (Standard Methods Agar), R2A Agar reported improved recovery of stress and chlorine-tolerant bacteria from drinking water systems. R2A Agar is recommended in standard methods for pour plate, spread plate, and membrane filtration methods for heterotrophic plate counts. • Product meets EPA, EP, Harmonized USP/EP/JP, PF, and SMWW reference methods and performance criteria.• R2A should be used by trained professionals within a laboratory setting. • Product is not intended for use in the diagnosis or treatment of disease or other human conditions.