Nature2 Duoclear 25 Replacement Cartridge | W28000 Nature2 Duoclear 25 Replacement Cartridge | W28000. This product offers a range of features such as Easy to install and compatible with most swimming pool filtration systems, Mineral sanitizer and chlorine dispenser in one, Control chlorine output with easy-to-read adjustment handle, Designed to sanitize in-ground swimming pools up to 45,000 gallons. Technical specifications and specific features include: Weight: 1.3 kg. Features and Benefits: Easy to install and compatible with most swimming pool filtration systems Mineral sanitizer and chlorine dispenser in one Control chlorine output with easy-to-read adjustment handle Designed to sanitize in-ground swimming pools up to 45,000 gallons Technical Specifications & Specific Features: Weight: 1.3 kg