EPA Method 502.2 Internal Standard Back Catalog number: 91703 Manufacturer: ABSOLUTE STANDARDS Availability: In the manufacturer's stock Price on request - + Recommended 1579.4-K-ME Metformin hydrochloride, 1000µg base/mL, Solvent-methanol, Unit 1mL, # of units-1, Cas.no. 1115-70-4 Price on request PCN-MXA Native PCN Solution/Mixture, 1.2ml, nonane Price on request 674330 Pentachloroaniline, 100mg Price on request