100% waterproof. Helps prevent cracks..
Features: Prevents Surfact Cracks Caused by Substrate Movement; Provides Protective Barrier Between Surface & Substrate; Wet Area Completely Sealed; Ideal for Wetrooms; Install Tiles Immeadiately After Matting Application; For Interior & Exterior Projects. Specifications: Powder based adhesive must be used. Adhesive used with tiles will determine the adhesive used with matting.