Stonecare4U's Limestone Sealer Colour Boost is a professional-grade sealant for external natural stone that protects against stains and soiling. The colour-boost formula delicately enhances the stone’s natural colours. It is suitable for all types of natural stone including sandstone (exceptions apply), limestone, slate, granite & others. Coverage is between 4-6 sq metres per litre on textured and riven surfaces, and up to 15 sq metres per litre on smooth, honed or polished surfaces. Please note this product is not suitable for Kandla Grey (mid & light grey) sandstone. For application, remove any loose debris from the work surface and ensure adequate safety wear is used. Leave the surface for a minimum of 72 hours with clear and dry weather to ensure it is completely dry. The application temperature range should be about 15° to 23°C. Apply the first coat with a low-pressure sprayer, roller, natural fibre brush or sponge. Do not dilute. Remove any excess sealer from the surface after 20 to 30 minutes. Apply a second coat approximately 45 to 60 minutes later for best results. After application, the stone surface must be kept completely dry through the curing process, which can take up to 72 hours. The sealer will alter the colour/appearance of the stone surface, so it is advised to test in an inconspicuous area prior to use. Surfaces that are not to be sealed should be protected with masking material. Clean sealed areas with a mild, pH-neutral cleaner or a very low concentration of Stonecare4U outdoor cleaner range. Do not use harsh or abrasive cleaning agents as this can have a negative effect on the treated surface. Not recommended for use on non-porous surfaces.