The PCM (Phase Change Material) in the Phase Change Cooling Inserts freezes in ice water or a refrigerator.

The Phase 2A Vest utilizes cooling packs to provide hours of relief from heat stress. When chilled for 35-45 minutes the packs change from a clear liquid to a white semisolid and will remain cool for two to three hours.

When chilled for 35-45 minutes the PCP2 Cooling Pack changes from a clear liquid to a white semisolid and will remain cool for two to three hours.

Stay cool in hot summer weather. This highly versatile, 100% cotton vest offers greater flexibility and more cooling choices.