WP Total Hardness Back Catalog number: 54156 Manufacturer: ABSOLUTE STANDARDS Availability: In the manufacturer's stock Price on request - + Recommended 9411.13-200MG Ritalinic acid (threo), neat, Solvent-neat, Unit 200mg, # of units-1, Cas.no. 54631-24-2 Price on request 676594 D8-4,4'-DDT, 100 µg/ml, Acetone, 1ml Price on request 57064 Gadolinium (Gd) Price on request