The KS-G 6B guard column has a polystyrene divinylbenzene (PSDVB) base with a sulfonate functional group and sodium counterion. Recommended for use with SUGAR KS series column. Fulfills USP L22 and L58 requirements. Shipping solvent: water. Stainless steel coupler 220-91524-97 or PEEK coupler 220-91524-99 (double ended) or 220-91524-98 (PEEK tube and fittings) is required.