The GIST C18 is made from ulta-inert silica for low adsorbtion of ionic compounds and highly symmetrical peaks. Extended pH range of 1-10 compared to other G Series C18 allows reliable analysis under acidic or basic conditions. USP L1, pore size: 100A, surface area: 350 m2/g, 14% carbon load, pH range: 1 to 10, fully endcapped. A guard column is recommended to prolong the lifetime of the analytical column. Similar to Premier Elite 220-97341-98.