Essential Slate Sealer Matt Finish is a specialist sealant for external natural slate that produces a matt appearance. The non-toxic, environmentally friendly formula provides outstanding water repellency and stain resistance. The distinctive formula of Essential Slate Sealer Matt Finish dramatically reduces the treated surface's capillary water absorption while not congesting the pores or capillaries. This substantially reduces the possibility of organic soiling, moss and algae growth, and allows the surface material to "breathe" and transfer moisture vapour. The amount of coverage will vary depending on the type of surface application, but it should be up to 15m2/litre per coat. Available in 5L and 25L. HOW TO APPLY: 1. Remove any loose debris from the work surface before beginning your work, and make sure you have adequate personal protection, such as gloves , proper protective eyewear , a face mask , and appropriate clothing. 2. The surface must be completely clean and dry prior to application. A low-pressure sprayer , roller, natural fibre brush, or sponge can be used for application. 3. To ensure complete coverage, apply two coats of Essential Slate Sealer Matt Finish to saturation. DO NOT DILUTE. After 45-60 minutes, the surface should be dry. If rain is forecasted or begins, cease production of treatment immediately and cover newly treated areas; the surface must remain completely dry for the first 6 hours after application. PLEASE NOTE: Essential Slate Sealer Matt Finish may cause colour changes on some surfaces; always test the product in an unnoticeable area before using it. Masking tape  should be used to protect surfaces that are not to be sealed. HIGHLY POLISHED, CERAMIC/GLAZED, DENSE OR NON-POROUS SURFACES ARE NOT RECOMMENDED FOR USE.