EPA Method 8121 Surrogate Standard Back Catalog number: 81204 Manufacturer: ABSOLUTE STANDARDS Availability: In the manufacturer's stock Price on request - + Recommended 677012 1,2-13C2 15N-Glyphosate, 100 µg/ml, Water, 1ml Price on request 679813 Sulfameter, 100 µg/ml, Methanol, 1ml Price on request 52013A Calibration Standard Mix 4 Price on request