Speedo Biofuse Swim Training Fins Latex free. 100% super soft silicone that is durable and resists deterioraton from sun and chlorine Latex free, so friendlier to the environment Stiff blade for maximum power and strength building with soft non chafing contoured foot pocket for excellent comfort Speedo trademarked Biofuse design construction that combines hard and soft silicone to enhance performance and provide unparalleled comfort Refer size chart to select the perfect fins.