WP Total Hardness Back Catalog number: 54156 Manufacturer: ABSOLUTE STANDARDS Availability: In the manufacturer's stock Price on request - + Recommended 13800-0280-100IO5 Phthalic acid, di-n/iso-C7-11-alkyl esters, 100µg/ml in Isooctane, 5ml Price on request 0646.30-100-IO Neohop-13(18)-ene, 100µg/mL, Solvent-isooctane, Unit 1mL, # of units-1, Cas.no. 21681-17-4 Price on request 90523 1,1,2-Trichlorotrifluoroethane Price on request