Expert Worldwide SK removes difficult stains that occur in the manufacturing and processing of textiles. SK effectively removes oil, grease, dirt, pencil, cosmetics and the widest variety of oil-based stains. The NEW formula has a reduced methylene chloride content (50 percent) to elevate the calculated threshold limit value (TLV). SK contains only premium, virgin solvents to reduce chances of solvent rings. SK is fast-drying and great for use on all types of fabrics including: cotton, wool, polyester and blends..