Calibration Standard Set Back Catalog number: 52042 Manufacturer: ABSOLUTE STANDARDS Availability: In the manufacturer's stock Price on request - + Recommended 54533 Ammonium (NH4+) Price on request L20020900IO PCB No. 209 10 µg/mL in Isooctane, 10ml Price on request M-8040-16 Phenol, 1000µg/ml in MeOH, 1ml Price on request