ResinTech CG8-BL-HP is a high purity strong acid cation resin in sodium form. It is dark brown in color and made from a 8% cross-linked gel. The HP (high purity) designation means it is Gold Seal Certified by the WQA for use in potable water applications. CG8-BL-HP is intended for softening and other salt form applications that require potable water certification.