Tech 10 Supervented Boots - Rainbow - US 11Construction uses a highly breathable, perforated microfiber with internal perforated padding, Highly ventilated perforated padding for optimized ventilation and airflow, TPU features is combined with ventilation zones and a new air flow system sole for breathability and superior ventilation, Two large inlet ports on front of boot with exhausts at back for optimized levels of airflow and heat exchange, 3D Higher Spring insole creates an effective cooling system using air channels within the sole for op