Minerals ion cartridge brings you clean and crystal clear spa water without high levels of heavy chemicals.Active ingredient is zinc.(inert ingredients are vitamin c,calcium sulfate,zeolite,attapulgite-type clay,zinc oxide and magnesium oxide.)A difference you can see,smell and feel,spa mineral cartridge improves water quality.Easy to install and low maintenance,compatible with most spa maintenance products.Mineral filter stick is a uncomplicated option for you,enjoy your relaxing spa experience with a mind at ease.Controlled mineral ion release technology, automatically dissolving trace amounts of mineral elements into the water.Mineral Stick works with existing filtration system,designed to fit most spa and hot tubs filters,available for 24 hours flow.", Note: 1. Please allow 1-3 mm error due to manual measurement and 1-3g weight error make sure you don't mind before ordering. 2. Due to the lighting of the photos and the difference of monitors, the pictures may not reflect the actual color of the real item. Please make sure you don't mind before ordering, thank you! About Shipping: 1.please pay attention to your delivery address such as: name, street, house number, doorbell/email without name, etc. is correct, or the order will not be delivered correctly. 2.All items will be shipped within 3 business days after the payment is received. Most times you will receive them within 8-12 days then. The specific delivery time is depend on circumstances. 3.During the shopping process, if you have any questions, please feel free to consult us, we will reply you within 24 hours Hope you have a pleasant shopping experience!