Ahlstroms high purity cellulose extraction thimbles are most commonly used in soxhlet extraction units for the separation of individual components from a mixture of solids and semisolids by solvent extraction. The use of a Soxhlet extractor provides a safe method of extraction with toxic or other noxious solvents. Ahlstrom extraction thimbles are recommended for the estimation of fats in food, analysis of lacquer and binder in paints, vitamin A and carotene extractions, and extraction of organic compounds from reaction mixtures. Thimble walls are approximately 1.5 mm thick and have been found to perform satisfactorily in applications requiring either a single or double wall thickness.