FROG @Ease Floating Sanitizing System + Replacement SmartChlor Cartridge 3-Pack Plus Free Hot Tub Care Guide, Self-Regulating Hot Tub Sanitizer BundleBrand: FROG Features: Eliminates organic contaminants 2 ways with a low level of chlorine and FROG Sanitizing Minerals. Minerals last 4 months, SmartChlor lasts up to 4 weeks depending on hot tub size and use; floats when working, flips when empty, ideal for hot tubs up to 600 gallons You use up to 75% less chlorine* with FROG @ease, making water easier on skin, hair, swimsuits, and your hot tubs surfaces. FROG sanitizing minerals eliminates organic