Sigvaris 840 Soft Opaque compression sock series contains lasting microfiber softness without chemical additives. Comfortable wide Top Band prevents Knee-highs from rolling. Advanced moisture management to keep legs cool and dry. Double-covered inlay yarns for ease of donning and removal. The PFS system provides a custom-like fit, superior comfort, and application of accurate compression levels, resulting in patient compliance and medical effectiveness. Double-covered yarns ensure durability and a long product life.