EPA Method 8240A Internal Standard Back Catalog number: 22003 Manufacturer: ABSOLUTE STANDARDS Availability: In the manufacturer's stock Price on request - + Recommended 33258 Dalapon acid Price on request 681689 2,4-Dimethylphenol, 100 µg/ml, Methanol, 5ml Price on request 681504 D8-Benzidine, 10mg Price on request