Proteinase K is a nonspecific serine protease that is active in the presence of SDS or urea and over a wide range of pH, salt concentrations and temperatures. This preparation is made at a concentration of 20 mg/ml in a storage buffer of 50 mM Tris, pH 8, 3 mM CaCl2, 50% Glycerol. Pack size is 1 x 1.25mls