Ronseal Thompson's Stain Block Damp Seal 2.5 litreA high performance seal for sealing and covering damp, water and other household stains in one coat. Micro porous formulation allows trapped moisture to escape. Can be applied directly to damp surfaces and permanently stops the reappearance of stains. The one coat formulation allows the surface to be decorated in 4 hours. Coverage to 7m L depending on the porosity of the substrate. Allow 4 hours between each coat. After the second coat, leave for a