Internal Standard Back Catalog number: 92467 Manufacturer: ABSOLUTE STANDARDS Availability: In the manufacturer's stock Price on request - + Recommended 677257 Tetrachloroethene, 1ml Price on request BCR-311 6-Nitrobenzo[a]pyrene, 10mg Price on request 677497 Pentachlorophenol, 10 µg/ml, Acetonitrile, 10ml Price on request