[Natural Spa Experience]: Spa mineral sticks can automatically add trace minerals to the hot tub, reduce impurities in the hot tub, Make the water clearer and cleaner, and make you as comfortable as in a pure natural hot spring [Perfect Compatibility]: The minimum filter length required for spa mineral stick is about 6.5 inches, and the minimum filter pore size is 1-1/4 inches; It is suitable for spas and hot tubs up to 500 gallons/2000 liters [For 4 Months]: Spa mineral stick has a maintenance time of up to 4 months. Just simply drop the spa stick into your existing device and let the hot tub stick do their work.You can enjoy a carefree spa experience for 4 months [Easy to Install]: This silver nitrate sticks comes with a complete manual. The installation can be completed quickly according to the steps in the manual, and is not affected by heat. It can be installed under existing traffic. Just put the spa wand into the existing filter and let the hot tub wand work [Suitable for Most Spas and Hot Tubs]: Spa mineral sticks perfect for jacuzzi, alcove bathtub, walk-in bathtub, whirlpool bathtub, hot tub boat and most easy to use standard bathtubs, just a few seconds installation.