[Safe Material] These well-made hot tub mineral rods are made of high-quality ABS plastic, sturdy and odorless. The minerals contained will not cause any harm to the human body, please feel free to use it. The minerals inside the hot tub mineral rod can effectively absorb some impurities in the water, creating a better and safer water environment for you to enjoy spa treatments. Features: Easy to Install * Hot Spring Mineral Rods are not affected by heat and can be installed over your existing water flow. Simply place the spa wand into your existing filter and let the new wand do its work. Natural minerals* ensure your spa is odor-free, improving your spa's performance and giving you crystal clear, clean, fresh water without harmful chemicals. Works with most spas and hot tubs* Fits Jacuzzis, inflatable tubs, alcove tubs, walk-in tubs, whirlpool tubs, hot tub boats and the easiest to use standard tubs in seconds Install. IDEAL CHOICE * Our hot tub rod spas have capacities up to 500 Gallons/2000L. Use our spa cartridges, which are low maintenance and cost effective and last up to 4-6 months, helping to save you time and money. Natural hot spring experience* Natural hot spring mineral paste can automatically add trace minerals in the hot spring, reduce impurities in the hot spring, make the water clearer and cleaner, and make you feel as comfortable as being in a pure natural hot spring. Package includes only *2 pieces of yellow spa filter sticks, other accessories are not included