The Chill-Its 6283 Rechargeable Phase Change 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 2 hours of enhanced cooling. HOW TO ACTIVATE For convenience on any job site, there are multiple methods for activating this cooling charge pack. Either place the pack in