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