EPA Method 552 Internal Standard Back Catalog number: 30055 Manufacturer: ABSOLUTE STANDARDS Availability: In the manufacturer's stock Price on request - + Recommended 95650 8270 Add-On Mix Price on request 8648.12-50-NN 1,2,4,6,7-Pentachlorodibenzo-p-dioxin,50 µg/mL,n-nonane,1mL, Price on request 96571 Pregnenolone Price on request