EPA Method 524 & 624 - Internal Standard Back Catalog number: 19794 Manufacturer: ABSOLUTE STANDARDS Availability: In the manufacturer's stock Price on request - + Recommended DF-1234678-S 1,2,3,4,6,7,8-Heptachlorodibenzofuran , 1.2ml x 50ug/ml, nonane Price on request 92257 Semi-Volatile Surrogate Standard Price on request 31161 1,2-Dibromoethane Price on request