PRO AIR II - The shoe that breathes, featuring two ventilated mesh ports coupled with an underfoot air circulation system that allows your Quarks to breathe with every step you take. The Pro-Air System is designed to keep you cool and dry all day long. GRIP STOP RUBBER Designed to give you the edge on any surface. Our high performance tread design provides outstanding grip, wet or dry. The James Test Certification for slip resistance rating is an outstanding .92! DRYZ Moisture Management to keep feet dry and comfortable.