WP Total Hardness Back Catalog number: 54156 Manufacturer: ABSOLUTE STANDARDS Availability: In the manufacturer's stock Price on request - + Recommended 42002 EPA Method 601 Analytes Price on request 71009 n-Propanol, 1000µg/ml in MeOH, 1ml Price on request 685309 3-Methoxytyramine hydrochloride, 25mg Price on request