SPETEC® WT400 is a single component hydrophilic caulk designed to swell and/or expand in the presence of water creating a watertight seal around pipe penetrations, cold joints, and other water stop locations. SPETEC® WT400 should be applied onto a dust-free, oil-free surface to maximize bond strength. SPETEC® WT400 should be applied at a minimum bead of 10mm with a minimum concrete cover of 7cm. SPETEC® WT400 must be fully confined to properly expand seal the surface. This material can be applied underwater onclean surfaces.