These are the Sherwood Fusion Scuba Diving Open Heel Fin w/ Spring Strap They Feature: The best features of today&';s fin technologies State of the art elastomers for a flexible yet ultra durable fin Tremendous power and propulsion in an attractive and rugged fin Performance engineered center channel and side rails direct water flow off the end of the fin for uncompromising power and efficiency Water does not pour" from the sides of the blade Unique blend of polymers provide increased flexibility and performance Optimized side rail structure provides the blade shape and snap that divers need in a power performance fin Stainless steel spring straps allow easy one-hand removal with a secure fit Will not deform from being overstretched Comfortably shaped foot pockets ensure no wasted energy exchange from foot to fin Sherwood took the best features of today&';s fin technologies and fused them together to come up with the Sherwood Fusion Fin. "