XQL Memory Foam Particles U-shape Headrest Travel Pillow Green Cotton Imported Fabric: Cotton, Fill: Foam particles Hypoallergenic materials. Natural and environmentally safe foam particles, each particle is about 0.5-0.8 mm diameter. Unique invisible zipper design. Famous zipper manufacturer, demanding binding zipper, invisible in the fabric, the increase under the premise of aesthetic maintain functional, more comfortable. Professional buckle brand NIFCO. NIFCO have a high visibility in the professional outdoor climbing areas, the product can be guaranteed to work at minus 25  environment. VERSATILE. It can be used anytime, anywhere conveniently while traveling in a car, train and plane.