Components: Assay Buffer 10X 100 mL; Chromagen Reagent 1 vial; Stop Solution 100 mL; Catalase Positive Control .25 mL; Peroxidase from horseradish, Type VI-A, essentially salt-free, lyophilized powder, 250-330 units/mg solid (using pyrogallol), 950-2000 units/mg solid (using ABTS) 5 mg; Hydrogen peroxide solution, contains ~200 ppm acetanilide as stabilizer, 3 wt. % in H2O