Calcium Hardness

2,2',3,3',5,5',6,6'-Octachloro[13C12]biphenyl, 1.2ml x 50ug/ml, nonane

alpha alpha alpha (20R,24S)-24-Methylcholestane, 50µg/mL, Solvent-isooctane, Unit 1mL, # of units-1, Cas.no. 511-20-6

Chlorfenvinphos, 250mg