The short blade rubber has excellent maneuverability and achieves a natural fin kick, making it a basic model that is suitable for first snorkeling and diving. These fins are meant to be worn directly with bare feet. Compatible estimated size (bare feet); XS size: 7.9 - 8.7 inches (20 - 22 cm); External dimensions: 16.3 x 7.2 inches (415 x 184 mm); S size: 8.7 - 9.8 inches (22 - 24 x 194 mm); MS size: 9.9 - 7.9 inches (4 inches (4 inches (20 inches (20 inches (20 cm); L size: 1 inches (28 cm). 510 x 2 Size XL: 11.0 - 11.8 inches (28 - 30 cm), Outer Dimensions: 21.6 x 8.3 inches (548 x 210 mm).