Find and tackle the trails with the new, lightweight and breathable Ultra III trainers from Vivobarefoot. With an innovative design, these ultra-flexible lace-ups are perfect for on-the-go fun and are a must-have within any shoe collection. Breathable perforated synthetic rubber upper. Soft and breathable synthetic lining for abrasion-free wear. Performance insole for underfoot support. Ultra-thin, flexible and foldable. Patented, ultra-thin, puncture resistant rubber sole.