EPA Method 551.1 Performance Check Sol’n Back Catalog number: 30115 Manufacturer: ABSOLUTE STANDARDS Availability: In the manufacturer's stock Price on request - + Recommended 673666 Phosphamidon, 100 µg/ml, Ethyl acetate, 5ml Price on request 73371 Trioctyl trimellitate, 1000μg/ml in methylene chloride, 1ml Price on request 97958 Method 525.2 Solution B Price on request