EPA Method 551.1 Standard Back Catalog number: 94519 Manufacturer: ABSOLUTE STANDARDS Availability: In the manufacturer's stock Price on request - + Recommended 677634 Paraquat dichloride, 100 µg/ml, Methanol, 1ml Price on request 677991 Pyrazophos, 100 µg/ml, Toluene, 1ml Price on request 50042 Anion Mix #1 Price on request