Hyperkewl evaporative cooling neck Shades offer both active cooling and protection from the sun’s harmful effects. Hives lime outer layer allows visibility and optimum airflow. Hyperkewl inner layer gives 5-10 hours of active cooling per soak. Attaches to hard Hat or bump cap harness with hook and loop closures. Keeps neck cool and protected . Hook and loop to attach to hard Hat or bump cap harness . Hyperkewl inner layer cools for 5-10 hours per soak . Hives lime color offers visibility and safety . No bulging GELS or harmful chemical crystals.