EPA Method 507 - Performance Check Solution Back Catalog number: 19130 Manufacturer: ABSOLUTE STANDARDS Availability: In the manufacturer's stock Price on request - + Recommended 9424.8-K-ME Valproic acid, 100µg/mL, Solvent-methanol, Unit 1mL, # of units-1, Cas.no. 99-66-1 Price on request AC-AQ40-030 Aqueous ethanol control EtOH AQ (4.0g/L), 10 x 3.0ml Price on request 79092 Indole Price on request