Refills for use in either the Spa Frog Floating System or for users of the Spa Frog In-line System factory-installed in selected newer spa models including: Emerald Saratoga Caldera Marquis Morgan Watkins Hot Spot Pacific Hot Tubs and Leisure Bay spas. Minerals used on setting #6 (max.) last 4 months.Used with companion Frog Bromine Cartridges..
