Ergodyne chill-its 6705 evaporative cooling Bandana is filled with a super absorptive evaporative acrylic polymer crystals that soak up moisture and provide instant cooling relief. Can be used for hours or for Quick relief. Reusable, just re-wet to activate. Great for outdoor activities, camping, Yoga, baseball, softball, soccer, running, biking, days at the Beach or on a boat, golf, landscaping, yard work, construction job sites, fishing, gardening, hiking.