Milwaukee BOLT Cooling Skull Cap is designed to keep you cool and comfortable on the jobsite. This innovative skull cap is activated by water and utilizes advanced microfiber technology to provide effective cooling. Simply run or submerge the cap under water for 30 seconds to fully activate it, then wring out any excess water. When dry, you can reactivate it by repeating the process. Once activated, the Cooling Skull Cap wicks away moisture and heat, ing up to four hours of cooling relief. It features a comfortable, four-way stretch material that fits well under Milwaukee Safety Helmets and Hard Hats. As part of the BOLT Accessory System, it allows users to secure multiple accessories simultaneously, enhancing convenience and functionality throughout your workday. Model Number: 48-73-4545