The Chill-Its 6283 Rechargeable Phase Change Ice Pack quickly activates to keep workers cool, productive and safe in the heat. This pack is specifically designed for compatibility with the Chill-Its 6483 Cooling Neck Gaiter—simply insert the activated pack into the interior back-of-neck pocket for up to two hours of enhanced cooling. For convenience on any job site, there are multiple methods for activating this cooling charge pack. Either place the pack in a cooler of ice water for 5 minutes, freezer for 9 minutes, refrigerator for 12 minutes or near an air conditioner for one to two hours. When activated, the phase change cooling material will maintain a 64° F (18° C) temperature for up to two hours. Simply recharge to reactivate. The cooling pack should be hand washed with a mild detergent and warm water. Dry with a paper towel or cloth. Do not machine wash or machine dry.Note: This is a non-returnable item.