High Quality MaterialOur Spa Mineral Sticks Are Made Of High Quality And Healthy Abs Material, Odorless And Fine Workmanship. Drops Into The Spa Filter Directly, Keeps The Water Fresh And Clear For A Long Time, Brings You A Natural And Healthy Spa. Can Effectively Filter Out A Variety Of Impurities, Keeping Spa Water In Good Quality And Keeping Your Tub Clean.Easy To Use And Replace Simply Place The Mineral Stick Parts Into Your Spa Filter Or Your Skimmer Basket And Let Them Do Their Job, No Other Complicated Process Is Needed. 2 Practical Parts To Be Replaced In Time. (Recommended To Replace It Once Every 3-4 Months.)Low MaintenanceWith Our Spa Filter Cartridge, Can Provide Up To 4 Months Of Service For Your Spa Filter, And Maintenance Cost Is Extremely Low, Helpful To Save Your Time And Cost, You Won'T Have To Check Or Change It For The Next Four Months.Widely ApplicableThese Spa Cartridges Are Suitable For Most Spas And Baths Whirlpool Tubs, Also Compatible With Inflatable Spas, Hot Tubs, Walk-In Tubs, Outdoor Pools, Baths, Plunge Pools And The Easiest To Use Standard Tubs.