• Low-chlorine spa sanitizing cartridge maintains a consistent 0.5–1.0 ppm free chlorine level at all times
• Lasts 3-4 weeks in spas up to 600 gallons
• Shock only once a month and use up to 75% less chlorine
• Minerals last up to 4 months, SmarChlor cartridges last 3-4 weeks in spas up to 600 gallons
• Floats in spa water and flips over when empty, indicating the SmartChlor cartridge needs replacing

As of March 2022, we are back in stock on this popular item. Limit 1 per customer.