One 2 mL flame-sealed ampule with 1.5 mL of PFAS standard containing 29 analytes at 50 ng/mL. The standard is suitable for matrices to include, but not limited to, drinking water and compatible with methods EPA 533, EPA 537, EPA 537.1 and other comparable methods. Branch configuration is linear for all analytes except for PFHxS, PFOS, NMeFOSAA, NEtFOSAA. These four analytes are made from sources which include both linear and branched isomers. The Certified Values presented on the Certificate of Analysis for these compounds is the total isomer concentration.