EPA Method 525.2 - 526 Internal Standard Back Catalog number: 91297 Manufacturer: ABSOLUTE STANDARDS Availability: In the manufacturer's stock Price on request - + Recommended N-12147-100MG Heptachlor, 100mg Price on request 13400-1150-100ME5 3-Chlorotoluene, 100µg/mL in MeOH, 5mL Price on request 676696 Pendimethalin, 100 µg/ml, Acetone, 1ml Price on request