Phase Change Cooling Headwear TechNiche's Phase Change Cooling Headwear Inserts maintain a comfortable 58 degrees F (14 degrees C) for heat stress relief. They are an effective solution to keep cool on the job.   Phase Change Cooling 6621 Brow Pads Hook & loop attaches easily to hard hat liner (hard hat not included) 100% cotton (excluding insert) Royal Blue One Size Include one (1) Phase Change Cooling Brow Pad Insert (6663)     Phase Change Cooling 6663 Brow Pad Inserts Use additional inserts for continuous cooling relief Include one (1) Phase Change Cooling Brow Pad Insert For Phase Change Cooling Brow Pads (6621)     Phase Change Cooling 6622 Crown Coolers Hook & loop attaches easily to hard hat liner (hard hat not included) 100% cotton (excluding insert) Royal Blue One Size Include one (1) Phase Change Cooling Crown Cooler Insert (6664)     Phase Change Cooling 6664 Crown Cooler Inserts Use additional inserts for continuous relief from the heat Include one (1) Phase Change Cooling Crown Cooler Insert For Phase Change Cooling Crown Coolers (6622)