ACQUITY UPLC™ BEH Shield RP18 columns combine Waters patented Shield Technology* with BEH Technology™ by incorporating an embedded carbamate group into the bonded phase ligand. Waters shield ligands consistently demonstrate increased retention of phenolic compounds versus straight chain alkyl columns. The alternate selectivity and excellent peak shape from the embedded polar group ligand, when combined with the wide pH range and ultra-efficiency of the 1.7 μm BEH particle, provide a necessary and powerful tool for UPLC™ method development.