TamSeal BR is a pre-formed adhesive hydrophilic waterstop designed to swell up to 200% in the presence of water, providing a watertight seal in cold joints on concrete structures. This highly advanced product is made up of butyl rubber, polypropylene elastomer, hydrophilic fillers and plasticizers, providing a more uniform and controlled volumetric expansion upon contact with water. TamSeal BR is self-adhesive and bonds to a wide variety of substrates. Its ability to swell allows it to penetrate into poorly consolidated concrete surfaces.