Ideal for first responders, firefighters, police officers, military personnel and others who may work in hot environments, SWEED cooling vests protects wearer from the health hazards of heat stress. Select from mesh, polyester or Nomex vests. Each vest contains a set of 22 PhaseCore 28 or 32 elements, which have an activation point of 82.4 or 89.6 F, respectively. The elements consist of a nontoxic, nonflammable salt mixture, sealed inside thermal-aluminum wrappers. When one’s body temperature rises above the activation point, the elements change from a solid to a liquid state, providing up to 4 hours of soothing, cooling relief. To recharge vest, just store elements in an environment less than the activation point. No need for First Line Technology LLC, Chantilly, Va., ice or refrigeration to change elements’ liquid state back to a solid consistency for reuse as a cooling agent. Although the elements recharge quicker in a cold area or refrigerator, only room temperature is required. Vests boast lightweight, comfortable and machine-washable design. Available in various sizes, each with padded shoulders.