Accu-Tab® Blue with Scale Inhibitor tablets are made of Calcium Hypochlorite and are eroded to provide a residual of chlorine in your pool. For use in Accu-Tab® Chlorination Systems.Tablets erode reliably, consistently and predictably because the multi-step manufacturing and quality control process. Will not clog the system, a common problem with knock-off three-inch tablets and briquettes. More pH-friendly than chlorine gas, liquid bleach or trichlor tablets, requiring fewer adjustment chemicals, which saves money and makes water balance easier to achieve. Tablet form disinfectant and oxidizer, contains 65-75% available chlorine content, for commercial aquatic use. Includes scale inhibitor (SI). NSF Standard 50 listed. Available in #60 lb. pails. MUST be used in Accu-Tab® chlorination systems in order to maintain manufacturer’s warranty. Failure to do so may result in damage to equipment and/or serious bodily injury.