EPA Method 548.1 Internal Standard Back Catalog number: 30078 Manufacturer: ABSOLUTE STANDARDS Availability: In the manufacturer's stock Price on request - + Recommended 12115.12-100-ME (±)-Sotalol-d6 hydrochloride (dimethyl-d6),100 µg/mL,MeOH,1mL, Price on request 11998.8-100MG 5-Methoxy-2-benzimidazolinone,neat,neat,100mg, Price on request N-12148-50MG Heptachlor epoxide (Isomer B), 50mg Price on request