WP Total Hardness Back Catalog number: 54597 Manufacturer: ABSOLUTE STANDARDS Availability: In the manufacturer's stock Price on request - + Recommended 9487.16-50-IO 3-Chlorofluoranthene, 50µg/mL, Solvent-Isooctane, Unit 1mL, # of units-1, Cas.no. 25911-51-7 Price on request 677850 D8-Naphthalene, 2000 µg/ml, Acetonitrile, 1ml Price on request 680156 2-Butanol, 5ml Price on request