Chlorilong® CLASSIC (formerly Chlorilong® 250) is a slow dissolving, uniform 250 g chlorine tablet for the permanent of swimming pools. It combines the power of carefully selected active ingredients and an innovative compression method, the A.P.O.® technology. This process produces very high quality tablets. They dissolve very homogeneously and release a regular amount of chlorine into the water, for better disinfection of the pool. The Silk effect formula enhances the anti-limescale effect throughout the season and makes the water even more pleasant after a few weeks. Free of copper sulphate: respects the pool coatings. Free of boric acid