KEEN Utility Men's Birmingham Carbon Fiber Toe Work Shoe Magnet/Bright Cobalt A great choice for warm-weather work conditions, this shoe is built with a highly breathable mesh upper, lightweight carbon-fiber toes, supportive KEEN.ReGEN midsole, and versatile, all-purpose outsole that can handle variable surface conditions with ease. KEEN Utility Men's Birmingham Carbon Fiber Toe Work Shoe Magnet/Bright Cobalt