EPA Method 8021B Internal Standard Back Catalog number: 19394 Manufacturer: ABSOLUTE STANDARDS Availability: In the manufacturer's stock Price on request - + Recommended 689725 Azoxystrobin (free acid), 100µg/ml in Acetonitrile, 5ml Price on request 11898.20-10MG Maprotiline hydrochloride,neat,neat,10mg, Price on request 677970 Chlorfenvinphos, 100 µg/ml, Toluene, 1ml Price on request