PureCare Elements 100% Tencel sheets are botanically crafted from raw wood pulp and provide an exceptionally smooth. cool to the touch sleep surface. Our premium Tencel fibers are woven in a sateen weave for long-lasting softness and comfort. Designed to provide the ideal fit for both standard and adjustable base mattresses up to 18 deep. our premium sheet sets feature:- Precision-Fit corners for a clean. crisp fit on the fitted sheet- A 1 Precision-Fit elastic cuff which prevents your fitted sheet from slipping off your mattress – Enveloping pillowcases that secure your pillow in the case throughout the night- An additional 4 of flat sheet for complete coverageSheet set includes: fitted sheet / flat sheet / two pillowcases (one pillowcase in Twin XL)All PureCare Elements sheets feature antimicrobial silver chloride to inhibit bacteria. mold and mildew that cause deterioration. stains and odors on this product.