DaFin Flex Swim Fins - GreyDaFiN Flex is the same design as our pro model but with a new softer, more flexible blade. Flex is great for beginning swimmers or as an addition to your quiver for recreational or distance swimming and snorkeling. The softer blade retains flexibility in cold water. More Info: Soft footpocket Flexible blade Fins float in salt water. Lightweight and great for travel. Fins can be worn on either foot. Made with quality, natural rubber.