EPA Method 8260B Surrogate Standard Back Catalog number: 23004 Manufacturer: ABSOLUTE STANDARDS Availability: In the manufacturer's stock Price on request - + Recommended 674233 Fenthion-oxon-sulfone, 10.0 µg/ml, Acetonitrile, Price on request 672998 17a-Ethinylestradiol, 250mg Price on request D193500 Darunavir, 10mg Price on request