Made of highly flexible material and TUSA flex is used in the blade material. Entry level divers and those who are not confident in their leg strength will create a stable propulsion. Recommended for snorkelers who want to swim long distances with light force on the water. The worlds best selling plastic fins won the Earth of the Good Design Department Award. ● SF-5000 (Regular Size): 9.4 - 11.0 inches (24 - 28 cm); External Dimensions: 23.6 x 8.9 inches (598 x 225 mm).