DERMATOLOGIST RECOMMENDED.*ANTI AGING. ANTI SLEEP CREASE. ANTI BED HEAD.™  OVER 95% OF USERS AGREED SLEEP CREASES, SLEEP LINES AND SLEEP WRINKLES WERE FEWER AND LESS NOTICEABLE.† Slipsilk.™ Laboratory Tested. Hypoallergenic. The beauty secret of celebrity hairstylists, dermatologists and beauty experts.™ Includes 1 x King / International Standard Pillowcase (20” x 36” | 51cm x 91cm) with invisible zipper closure | Machine washable | See care instructions for details.  This product is also available in a queen size.  Learn more about our studies and testing under "Test and Study Details".