Wedi MS polymer sealant 10.5 oz The Wedi Joint Sealant Cartridge is a low V.O.C. (<1%) variety component, modified-silane MS polymer that chemically reacts with moisture to deliver strong, flexible and tenacious bonds to variety of surfaces. This product is specially formulated to connect and seal Wedi assemblies in their typically challenging application environment. By forming water-tight seals on joints, seams and at installations and protrusions, this sealant prevents possible escape opportunities for water or water vapor. Its flexibility allows for dissipation of stress caused by shock, vibration or thermal movement.