The Ultra Aqueous C18 is a rugged, reversed-phase column with a well-balanced retention profile. It can effectively retain more types of solutes than a conventional C18 with high reproducibility and compatibility with many mobile phase conditions—even 100% aqueous. When used with a gradient, it eliminates the all-too-common issue of multiple compounds eluting near the column void time. USP L1, 100A pore size, 15% carbon load, non-endcapped. pH range 2.5 to 8.0, maximum temperature 80C.