BioGuard Silk Tabs and Silk Sticks are revolutionary new products exclusive to BioGuard and the first sanitizer made with SilkGuard Technology. These products differ from traditional chlorine because their special additives actually soften the water by attaching to hard water components and metal surfaces, which protects your pool equipment from scale, corrosion and staining, all while killing bacteria. These slow dissolving sanitizers contain SunShield Technology so that chlorine is protected from sunlight for long-lasting sanitation of pool water.