Mission Enduracool Techknit Cooling Towel, Black, Large 90% Polyester/10% Nylon Proprietary technology cools to 30 degrees below average body temperature when wet Reusable and machine washable; lightweight When wet, stays cool for hours; when dry, soft and absorbent To activate cooling technology soak towel, wring out excess and snap three times; to reactivate, simply re-soak and re-snap Large: 12" x 33"; X-Large: 15" x 36"