silica bead filling draws water vapor from the air and slowly releases it over time, for longer-lasting, safer, and more consistent heat therapy. Plus, the segmented construction of this welcoming wrap helps ensure that heat is evenly distributed for efficient treatment. Pop the cozy, warming wrap in the microwave, lay it around your shoulders, and indulge in heated relief while you sit back, relax, and soothe your aches and pains away. Soothing Moisture Technology for deeper heat penetration Exterior Fabric: 100% polyfleece Filling: Silica bead 28" x 7" 2.9 lbs Adjustable tab closure Washable & reusable