Nava 652005404 50lb Granular Dichlor 56%. Dichlor (sodium dichloroisocyanuric acid) is generally sold as a granular chlorine and typically has 56% available chlorine. Dissolves relatively fast for an quick increase in chlorine residual. Dichlor is stabilized to protect the chlorine from the ultraviolet rays of the sun. This prolongs the life of the chlorine and gives you a healthy swimming environment and cost you less to maintain the proper chlorine residual. Dichlor has relatively neutral pH which minimizes the need for acid or soda ash. Can also be used for a shock treatment.