The Dimension One Spas Vision Sanitizing Cartridge (01512-261) uses natural minerals to keep the water in your hot tub super clean. Replacing your vision sanitizing system has been shown to extend the life of your spa water for up to 6 months! The vision sanitizing system, 01512-261, naturally kills bacteria and algae while reducing the need for using lots of chemicals in your spa. This means, fewer spa refills and reducing the chlorine smell that many other hot tubs have while improving your spas water clarity and maximizing bather comfort. To get the most out of your Vision Sanitizing System, try using it with the Ozone system. (Note: Vision and bromine should not be used together).