FROG Serene in-Line Cartridges for Hot Tubs That Have Built in Cartridge Holders, FROG Serene Mineral Cartridge + 3 Bromine Cartridges (200 Grams)

This FROG Serene In-Line Cartridge Replacement Bundle gives you weeks and weeks of ahhmazing hot tub water, for use in FROG Serene In-Line System. The Bromine and Mineral Cartridges fit...