Features:Patented Filling. The moist heat zone is held snug and secure in place by the wide elastic strap with strap closure.Shapped to hug the bod.Convenient moist heat therapy.Non-allergenic Crystal Fill won t leak develop unpleasant odors or allow growth of mold & fungus.Moisture Absorbing: Fill crystals have honeycombed surfaces to absorb the maxiumum amount of moisture.Outer multi-ply fabric provides Vapor-barrier Cover.Cloud-soft fleece provides comfortable cover and cradles painful tissues in soothing comfort.