FROG @ease In-Line SmartChlor Replacement Chlorine Cartridge for use in Marquis Spas, Caldera Spas, Artesian Spas and Hot Springs Spas up to 600 gallons, Hot Tub Sanitizer, Cyanuric Acid Free

Perfect replacement, so easy to change out and keeps my hot tub clean and clear for 4 weeks.

We have ordered this consistently for the last few months as we have needed it. It always arrives fast and is super simple to use. We just pop it in and we are good to go. Other versions of this product are not as effective and do not last nearly as long as FROG does. The cost is actually cheaper here on amazon than from our local store, as well as where we bought our hot tub from. We will continue to order this as it is well worth the money.

This is the same product, and cheaper then at your local spa store. Quality product and works well—keeps my hottub fresh and clean!

Easy to use and best price I have found

Works great consistently. We can keep an accurate water care routine in place to maintain our system efficiently without hassle. They Also offer an app to help assist with scheduling, products, and digital water chemistry via the test strips and your smart phone camera