Columbia - River Trainer (Tusk/Columbia Navy) - Men's: Stylish, lace-up aquatic trainer. Quick-drying synthetic nubuck uppers. Side mesh drainage panels. Internal EVA midsole. Non-marking, siped sticky carbon rubber cupsole. Micro-mesh lining for comfort and breathability. Stretch Micro-mesh collar for a snug fit. Designed to be worn without socks.