More Flex  Standard  S1 A standard setting S1 flexible, cementitious wall and floor tile adhesive. Kelmore’s More Flex  Standard S1 is a highly polymer modified, flexible, standard setting, cementitious tile adhesive for walls and floors. This deformable adhesive hasexcellent bond strength and flexibility ensuring various types of tiles, such as porcelain, ceramic and most natural stone can be confidently fixed to a wide range of backgrounds, including those subject to limited movement and vibration. Allowing bed depths up to 15mm, More Flex  Standard S1 has a long pot life of 4 hours and an excellent open time of 40 minutes, whilst still enabling the tiles to be grouted after 16 hours. Showing its true versatility, this adhesive is suitable for interior and exterior use, as well as in wet areas, including swimming pools. It is suitable for use on underfloor heating systems, and it is particularly recommended for fixing large format tiles.