Polyester Mesh Insulating Lining Drawstring pocket and velcro rear strap closure Designed to allow ice to melt so the cold water runs and cools your head, neck, and body. YOU WILL GET WET! Reduces heart rate in warm or hot weather for comfort and increased athletic performance. Polyester Mesh Insulating Liner Drawstring pocket and velcro rear strap closure Designed to allow ice to melt so the cold water runs and cools your head, neck, and body. YOU WILL GET WET! Reduces heart rate in warm or hot weather for comfort and increased athletic performance. For long runs or hikes, bring a cooler to refill your ICED Cap when the ice melts! Ultra runners, have your crew ready with ice refills at aid stations! Easy-to-use drawstring pocket contains ice or works as storage for gels/snacks/trash. Perfect for runners of all levels or for other activities like gardening, tennis, camping, lounging by swimming pools, going to the beach, and fishing Fits most adults; adjustable rear strap. We recommend adjusting the size AFTER putting ice in the ICED Cap.