EPA Method 524 & 624 - Internal Standard Back Catalog number: 19794 Manufacturer: ABSOLUTE STANDARDS Availability: In the manufacturer's stock Price on request - + Recommended 2688.34-10UG 17 alpha(H),21ß(H)-(22S)-Tetrakishomohopane , neat, Solvent-neat, Unit ca. 10µg , # of units-1, Cas.no. 67069-13-0 Price on request 674482 Citrate-Extraction-Mix Price on request 2322.13-K-IO 9-Fluorenone, 1000µg/mL, Solvent-isooctane, Unit 1mL, # of units-1, Cas.no. 486-25-9 Price on request