EPA Method 500 Series Internal Std #4

Fenthion-oxon-sulfoxide, 50mg

4,5-Dichloro-2-octyl-isothiazolone, 100mg

1,5-Dihydroxy-9,10-anthraquinone, neat, Solvent-neat, Unit 10mg, # of units-1, Cas.no. 117-12-4