A smart combination of soft aggressive tread and thoughtful support innovations make The North Face Arnuva 100 TR trail running shoe is an ideal choice for ultra distance athletes who tend hit their strides off road. The Arnuva 100 TR features an incredibly lightweight and supportive dual density compression molded EVA midsole above a high traction Tenacious Grip rubber outsole but everything is assisted with a rear foot compression cage for added stability. The North Face also added X-2™ polymer compounds in the midsoles to dampen vibrations and add resiliency that won't "pack in" as quickly as other cushy endurance shoes. Another nice extra inside the shoe is a Sure Grip heel lining panel that minimizes friction and helps eliminate heel slip. Beneath the Arnuva 100 TR is The North Face Tenacious Grip rubber outsole an innovative compound that grips exceptionally well off-road even in a variety of weather and temperature conditions.