Come and Check Our Promo Solutions.This Neck Cooler Scarf is made of the cotton material and is great to use during hot weather for keeping cool. Simply soak the scarf in water and wait until the scarf has expanded to a bulge,indicating that the sewn crystals inside have absorbed the maximum amount of water they can contain. The absorbed water then slowly removes heat from your skin as it evaporates in much the same way our own body does through sweating. Great for family-oriented summer campaigns. Pls check inventory and detailed info with us before placing your orders.