EPA Method 507 - Internal Standard Back Catalog number: 19031 Manufacturer: ABSOLUTE STANDARDS Availability: In the manufacturer's stock Price on request - + Recommended 11675.12-100-IO 2,3,6-Trichlorobiphenyl ,100 µg/mL,isooctane,1mL, Price on request 33571 Dichlorodifluoromethane, 20mg/mL in MeOH, 1ml Price on request 679308 Dimethyldioctadecylammonium chloride, 25mg Price on request