Spa Frog @ease Smartchlor Replacement Cartridge - 3 Pack

Spa Frog @ease Replacement SmartChlor Chlorine Cartridge - 3 Pack Low-chlorine spa sanitizing cartridge maintains a consistent 0.5 - 1.0 ppm free chlorine level at all timesShock only once a month and use up to 75% less chlorineFloats in spa water and flips over when empty, indicating the SmartChlor cartridge needs replacingLasts 3-4 weeks in spas up to 600 gallonsDesigned for use with Spa Frog @ease Mineral System - Mineral Cartridge not included The King Technology Floating SmartChlor Cartridges help to maintain a steady presence of chlorine in your spa, keeping your water sanitized and safe.