EPA Method 524 & 624 - Internal Standard Back Catalog number: 19494 Manufacturer: ABSOLUTE STANDARDS Availability: In the manufacturer's stock Price on request - + Recommended 31282 EPA Method 507 Nitrogen Phosphorus Pesticides Price on request 11291.6-100-NN alpha-BHC-13C6,100 µg/mL,n-nonane,1mL, Price on request 673650 Paraoxon-methyl, 100 µg/ml, Ethyl acetate, 5ml Price on request